1
|
Zeuli R, Karali M, de Bruijn SE, Rodenburg K, Scarpato M, Capasso D, Astuti GDN, Gilissen C, Rodríguez-Hidalgo M, Ruiz-Ederra J, Testa F, Simonelli F, Cremers FPM, Banfi S, Roosing S. Whole genome sequencing identifies elusive variants in genetically unsolved Italian inherited retinal disease patients. HGG ADVANCES 2024; 5:100314. [PMID: 38816995 PMCID: PMC11225895 DOI: 10.1016/j.xhgg.2024.100314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 05/27/2024] [Accepted: 05/28/2024] [Indexed: 06/01/2024] Open
Abstract
Inherited retinal diseases (IRDs) are a group of rare monogenic diseases with high genetic heterogeneity (pathogenic variants identified in over 280 causative genes). The genetic diagnostic rate for IRDs is around 60%, mainly thanks to the routine application of next-generation sequencing (NGS) approaches such as extensive gene panels or whole exome analyses. Whole-genome sequencing (WGS) has been reported to improve this diagnostic rate by revealing elusive variants, such as structural variants (SVs) and deep intronic variants (DIVs). We performed WGS on 33 unsolved cases with suspected autosomal recessive IRD, aiming to identify causative genetic variants in non-coding regions or to detect SVs that were unexplored in the initial screening. Most of the selected cases (30 of 33, 90.9%) carried monoallelic pathogenic variants in genes associated with their clinical presentation, hence we first analyzed the non-coding regions of these candidate genes. Whenever additional pathogenic variants were not identified with this approach, we extended the search for SVs and DIVs to all IRD-associated genes. Overall, we identified the missing causative variants in 11 patients (11 of 33, 33.3%). These included three DIVs in ABCA4, CEP290 and RPGRIP1; one non-canonical splice site (NCSS) variant in PROM1 and three SVs (large deletions) in EYS, PCDH15 and USH2A. For the previously unreported DIV in CEP290 and for the NCCS variant in PROM1, we confirmed the effect on splicing by reverse transcription (RT)-PCR on patient-derived RNA. This study demonstrates the power and clinical utility of WGS as an all-in-one test to identify disease-causing variants missed by standard NGS diagnostic methodologies.
Collapse
Affiliation(s)
- Roberta Zeuli
- Medical Genetics, Department of Precision Medicine, University of Campania 'Luigi Vanvitelli', Naples, Italy
| | - Marianthi Karali
- Medical Genetics, Department of Precision Medicine, University of Campania 'Luigi Vanvitelli', Naples, Italy; Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania 'Luigi Vanvitelli', Naples, Italy
| | - Suzanne E de Bruijn
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Kim Rodenburg
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Margherita Scarpato
- Medical Genetics, Department of Precision Medicine, University of Campania 'Luigi Vanvitelli', Naples, Italy
| | - Dalila Capasso
- Telethon Institute of Genetics and Medicine, Pozzuoli, Italy; Scuola Superiore Meridionale (SSM, School of Advanced Studies), Genomic and Experimental Medicine Program, Naples, Italy
| | - Galuh D N Astuti
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands; Radboud Institute of Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Christian Gilissen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands; Radboud Institute of Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - María Rodríguez-Hidalgo
- Department of Neuroscience, Biogipuzkoa Health Research Institute, Donostia-San Sebastián, Spain; Department of Dermatology, Ophthalmology, and Otorhinolaryngology, University of the Basque Country (UPV/EHU), Donostia-San Sebastián, Spain
| | - Javier Ruiz-Ederra
- Department of Neuroscience, Biogipuzkoa Health Research Institute, Donostia-San Sebastián, Spain; Department of Dermatology, Ophthalmology, and Otorhinolaryngology, University of the Basque Country (UPV/EHU), Donostia-San Sebastián, Spain
| | - Francesco Testa
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania 'Luigi Vanvitelli', Naples, Italy
| | - Francesca Simonelli
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania 'Luigi Vanvitelli', Naples, Italy
| | - Frans P M Cremers
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Sandro Banfi
- Medical Genetics, Department of Precision Medicine, University of Campania 'Luigi Vanvitelli', Naples, Italy; Telethon Institute of Genetics and Medicine, Pozzuoli, Italy.
| | - Susanne Roosing
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands.
| |
Collapse
|
2
|
Hiraoka M, Urakawa Y, Kawai K, Yoshida A, Hosakawa J, Takazawa M, Inaba A, Yokota S, Hirami Y, Takahashi M, Ohara O, Kurimoto Y, Maeda A. Copy number variant detection using next-generation sequencing in EYS-associated retinitis pigmentosa. PLoS One 2024; 19:e0305812. [PMID: 38913662 PMCID: PMC11195993 DOI: 10.1371/journal.pone.0305812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Accepted: 06/05/2024] [Indexed: 06/26/2024] Open
Abstract
Retinitis pigmentosa (RP) is the most common inherited retinal dystrophy and a major cause of blindness. RP is caused by several variants of multiple genes, and genetic diagnosis by identifying these variants is important for optimizing treatment and estimating patient prognosis. Next-generation sequencing (NGS), which is currently widely used for diagnosis, is considered useful but is known to have limitations in detecting copy number variations (CNVs). In this study, we re-evaluated CNVs in EYS, the main causative gene of RP, identified via NGS using multiplex ligation-dependent probe amplification (MLPA). CNVs were identified in NGS samples of eight patients. To identify potential CNVs, MLPA was also performed on samples from 42 patients who were undiagnosed by NGS but carried one of the five major pathogenic variants reported in Japanese EYS-RP cases. All suspected CNVs based on NGS data in the eight patients were confirmed via MLPA. CNVs were found in 2 of the 42 NGS-undiagnosed RP cases. Furthermore, results showed that 121 of the 661 patients with RP had EYS as the causative gene, and 8.3% (10/121 patients with EYS-RP) had CNVs. Although NGS using the CNV calling criteria utilized in this study failed to identify CNVs in two cases, no false-positive results were detected. Collectively, these findings suggest that NGS is useful for CNV detection during clinical diagnosis of RP.
Collapse
Affiliation(s)
- Masakazu Hiraoka
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
- Department of Ophthalmology, Kawasaki Medical School, Kurashiki, Okayama, Japan
| | - Yusaku Urakawa
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
- Department of Ophthalmology, Kobe City Medical Center General Hospital, Kobe, Japan
| | - Kanako Kawai
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
| | - Akiko Yoshida
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
| | - Junichi Hosakawa
- Department of Frontier Research and Development, Laboratory of Medical Omics Research, Kazusa DNA Research Institute, Chiba, Japan
| | - Masaki Takazawa
- Department of Frontier Research and Development, Laboratory of Medical Omics Research, Kazusa DNA Research Institute, Chiba, Japan
| | - Akira Inaba
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
| | - Satoshi Yokota
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
- Department of Ophthalmology, Kobe City Medical Center General Hospital, Kobe, Japan
| | - Yasuhiko Hirami
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
- Department of Ophthalmology, Kobe City Medical Center General Hospital, Kobe, Japan
| | - Masayo Takahashi
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
- Vision Care Inc., Kobe, Japan
- Research Organization of Science and Technology SR Center, Ritsumeikan University, Shiga, Japan
| | - Osamu Ohara
- Department of Frontier Research and Development, Laboratory of Medical Omics Research, Kazusa DNA Research Institute, Chiba, Japan
| | - Yasuo Kurimoto
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
- Department of Ophthalmology, Kobe City Medical Center General Hospital, Kobe, Japan
| | - Akiko Maeda
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
- Department of Ophthalmology, Kobe City Medical Center General Hospital, Kobe, Japan
- Research Organization of Science and Technology SR Center, Ritsumeikan University, Shiga, Japan
| |
Collapse
|
3
|
Bodenbender JP, Bethge L, Stingl K, Mazzola P, Haack T, Biskup S, Wissinger B, Weisschuh N, Kohl S, Kühlewein L. Clinical and Genetic Findings in a Cohort of Patients with PRPF31-Associated Retinal Dystrophy. Am J Ophthalmol 2024; 267:213-229. [PMID: 38909744 DOI: 10.1016/j.ajo.2024.06.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Revised: 06/12/2024] [Accepted: 06/13/2024] [Indexed: 06/25/2024]
Abstract
PURPOSE The purpose of our study was to assess the phenotypic and genotypic spectrum in a large cohort of patients with PRPF31-associated retinal dystrophy. DESIGN Retrospective cohort study. METHODS In this retrospective chart review study, we collected cross-sectional data on the phenotype and genotype of patients with PRPF31-associated retinal dystrophy from the clinics for inherited retinal dystrophies at the University of Tuebingen and the local RetDis database and biobank. Patients underwent thorough ophthalmological examinations and genetic testing. RESULTS Eighty-six patients from 61 families were available for clinical assessment, while genomic DNA was available for 111 individuals (index patients and family members). Fifty-three different disease-associated variants were observed in our cohort. Point mutations were the most common class. All but two patients exhibited features of a typical Retinitis pigmentosa (RP). One patient showed a cone-rod dystrophy pattern. One mutation carrier revealed no signs of a retinal dystrophy. There was a statistically significant better visual acuity for patients with large deletions in the 20-39 age group. Cystoid macular edema was common in those with preserved central retina and showed an association with female sex. CONCLUSION Our study confirms high phenotypic variability in disease onset and age at which legal blindness is reached in PRPF31-associated RP. Non-penetrance is commonly documented in family history, although poorly represented in our study, possibly indicating that true asymptomatic mutation carriers are rare if followed-up over lifetime with thorough ophthalmologic workup.
Collapse
Affiliation(s)
- Jan-Philipp Bodenbender
- University Eye Hospital, Center for Ophthalmology, Eberhard Karls University (J.P.B., L.B., K.S., L.K.), Tübingen, Germany
| | - Leon Bethge
- University Eye Hospital, Center for Ophthalmology, Eberhard Karls University (J.P.B., L.B., K.S., L.K.), Tübingen, Germany
| | - Katarina Stingl
- University Eye Hospital, Center for Ophthalmology, Eberhard Karls University (J.P.B., L.B., K.S., L.K.), Tübingen, Germany
| | - Pascale Mazzola
- Institute of Medical Genetics and Applied Genomics, Eberhard Karls University (P.M., T.H.), Tübingen, Germany
| | - Tobias Haack
- Institute of Medical Genetics and Applied Genomics, Eberhard Karls University (P.M., T.H.), Tübingen, Germany; Center for Rare Diseases, Eberhard Karls University (T.H.), Tübingen, Germany
| | | | - Bernd Wissinger
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, Center for Ophthalmology, Eberhard Karls University (B.W., N.W., S.K.), Tübingen, Germany
| | - Nicole Weisschuh
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, Center for Ophthalmology, Eberhard Karls University (B.W., N.W., S.K.), Tübingen, Germany
| | - Susanne Kohl
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, Center for Ophthalmology, Eberhard Karls University (B.W., N.W., S.K.), Tübingen, Germany
| | - Laura Kühlewein
- University Eye Hospital, Center for Ophthalmology, Eberhard Karls University (J.P.B., L.B., K.S., L.K.), Tübingen, Germany; Institute for Ophthalmic Research, Center for Ophthalmology, Eberhard Karls University (L.K.), Tübingen, Germany.
| |
Collapse
|
4
|
Zhuang J, Zhang R, Zhou B, Cao Z, Zhou J, Chen X, Zhang N, Zhu Y, Yang J. Mutation analysis of RHO in patients with non-syndromic retinitis pigmentosa. Ophthalmic Genet 2024; 45:147-152. [PMID: 38284172 DOI: 10.1080/13816810.2023.2294843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 12/09/2023] [Indexed: 01/30/2024]
Abstract
PURPOSE To identify RHO mutations in patients with non-syndromic retinitis pigmentosa (NS-RP). METHODS A total of 143 probands (46 family history and 97 sporadic cases) with NS-RP were recruited from Southeast China. The coding exons and adjacent intronic regions of RHO were PCR-amplified and sequenced by Sanger sequencing. The candidate variant was evaluated by the guidelines of American College of Medical Genetics and further validated through co-segregation analysis within the family. RESULTS Five heterozygous mutations in RHO were detected in 5 out of 143 probands, where the frequency of RHO mutations in our cohort was approximately 3.5% (5/143) and 10.8% (5/46) for probands and families with NS-RP, respectively. Three known disease-causing mutations including c.C1030T (p.Q344X), c.C173G (p.T58R), and c.G266A (p.G89D) were identified in three unrelated families. The other two previously unreported mutations c.557C>A (p.S186X) and c.944delA (p.N315TfsX43) were confirmed in Family RP-087 and Family RP-139, respectively. These mutations co-segregated with available affected individuals in each family were not observed in the unaffected family members or in the 112 unrelated controls. CONCLUSIONS This report expands the mutational spectrum of RHO gene associated with NS-RP and demonstrates the frequency of RP RHO mutations in Southeast Chinese populations.
Collapse
Affiliation(s)
- Jianfu Zhuang
- Ophthalmology, Xiamen Eye Center of Xiamen University, Xiamen, Fujian, China
| | - Rongcai Zhang
- Fujian Baimeng Biotechnology Research Center, Fujian BioMed Technology Co. LTD, Fuzhou, Fujian, China
| | - Biting Zhou
- Department of Ophthalmology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China
| | - Zongfu Cao
- National Human Genetic Resources Center, National Research Institute for Family Planning, Beijing, China
| | - Jie Zhou
- Department of Bioengineering and Biopharmaceutics, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian, China
| | - Xiaole Chen
- Department of Bioengineering and Biopharmaceutics, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian, China
| | - Nanwen Zhang
- Department of Bioengineering and Biopharmaceutics, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian, China
| | - Yihua Zhu
- Department of Ophthalmology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China
| | - Juhua Yang
- Department of Bioengineering and Biopharmaceutics, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian, China
| |
Collapse
|
5
|
Daich Varela M, Moya R, Azevedo Souza Amaral R, Schlottmann PG, Álvarez Mendiara A, Francone A, Guazi Resende R, Capalbo L, Gelvez N, López G, Morales-Acevedo AM, Ossa RH, Arno G, Michaelides M, Tamayo ML, Ferraz Sallum JM. Clinical and Genetic Characterization of RDH12-Retinal Dystrophy in a South American Cohort. Ophthalmol Retina 2024; 8:163-173. [PMID: 37714431 DOI: 10.1016/j.oret.2023.09.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 08/30/2023] [Accepted: 09/06/2023] [Indexed: 09/17/2023]
Abstract
PURPOSE To characterize the largest cohort of individuals with retinol dehydrogenase 12 (RDH12)-retinal dystrophy to date, and the first one from South America. DESIGN Retrospective multicenter international study. SUBJECTS Seventy-eight patients (66 families) with an inherited retinal dystrophy and biallelic variants in RDH12. METHODS Review of clinical notes, ophthalmic images, and molecular diagnosis. MAIN OUTCOME MEASURES Visual function, retinal imaging, and characteristics were evaluated and correlated. RESULTS Thirty-seven individuals self-identified as Latino (51%) and 34 as White (47%). Sixty-nine individuals (88%) had Leber congenital amaurosis (LCA)/early-onset severe retinal dystrophy. Macular and midperipheral atrophy were seen in all patients from 3 years of age. A novel retinal finding was a hyperautofluorescent ring in 2 young children with LCA. Thirty-nine patients (50%) had subsequent visits, with mean follow-up of 6.8 ± 7.3 (range, 0-29) years. Eight variants (21%) were previously unreported, and the most frequent variant was c.295C>A, p.Leu99Ile, present in 52 alleles of 32 probands. Individuals with LCA homozygous for p.Leu99Ile (31%) had a later age of onset, a slower rate of best-corrected visual acuity decrease, the largest percentage of patients with mild visual impairment, and were predicted to reach legal blindness at an older age than the rest of the cohort. CONCLUSIONS By describing the largest molecularly confirmed cohort to date, improved understanding of disease progression was possible. Our detailed characterization aims to support research and the development of novel therapies that may have the potential to reduce or prevent vision loss in individuals with RDH12-associated retinal dystrophy. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found in the Footnotes and Disclosures.
Collapse
Affiliation(s)
- Malena Daich Varela
- Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom.
| | - Rene Moya
- Departamento de Retina y Departamento de Genética Ocular, Hospital del Salvador, Universidad de Chile, Santiago, Chile
| | - Rebeca Azevedo Souza Amaral
- Ophthalmology Department, Federal University of São Paulo (UNIFESP), São Paulo, Brazil; Instituto de Genética Ocular, São Paulo, Brazil
| | | | | | | | | | | | - Nancy Gelvez
- Instituto de Genética Humana, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Greizy López
- Instituto de Genética Humana, Pontificia Universidad Javeriana, Bogotá, Colombia
| | | | - Rafael H Ossa
- Instituto de Genética Humana, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Gavin Arno
- Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Michel Michaelides
- Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Martha L Tamayo
- Instituto de Genética Humana, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Juliana Maria Ferraz Sallum
- Ophthalmology Department, Federal University of São Paulo (UNIFESP), São Paulo, Brazil; Instituto de Genética Ocular, São Paulo, Brazil
| |
Collapse
|
6
|
Khan AO. RPGRIP1-related retinal disease presenting as isolated cone dysfunction. Ophthalmic Genet 2023; 44:595-597. [PMID: 36762997 DOI: 10.1080/13816810.2023.2175224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/15/2023] [Accepted: 01/27/2023] [Indexed: 02/11/2023]
Abstract
PURPOSE Bialleic RPGRIP1 pathogenic variants are typically associated with severe Leber congenital amaurosis (non-recordable electroretinography [ERG]) and less commonly with cone-rod dystrophy. This report highlights isolated cone dysfunction as an alternative RPGRIP1-related presenting phenotype. METHODS Retrospective case series. RESULTS Four individuals (two sibships from two unrelated families) had low vision, nystagmus, photophobia, and a grossly normal retinal appearance since soon after birth. ERG confirmed non-recordable photopic function with normal scotopic function. Genetic testing revealed affected members from the two families to harbor two different homozygous RPGRIP1 variants (Family 1: c.3565C>T; p.Arg1189*; Family 2: c.2711_2741delinsATATTAG; p.Gly904_Lys914delinsAspIIeArg). Follow-up for Family 1 revealed deterioration of pan-retinal function (non-recordable ERGs by 11 and 7 years old) and thus a final diagnosis of cone-rod dystrophy. Follow-up for Family 2 showed stable retinal function (normal ERG scotopic tracings maintained at 12 and 21 years old) and thus a diagnosis of isolated cone dysfunction. CONCLUSIONS Isolated cone dysfunction that progresses to pan-retinal dysfunction or remains relatively stationary is an alternative phenotype related to biallelic RPGRIP1 pathogenic variants.
Collapse
Affiliation(s)
- Arif O Khan
- Eye Institute, Cleveland Clinic Abu Dhabi, Abu Dhabi, UAE
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, Ohio, USA
| |
Collapse
|
7
|
Sanjurjo-Soriano C, Jimenez-Medina C, Erkilic N, Cappellino L, Lefevre A, Nagel-Wolfrum K, Wolfrum U, Van Wijk E, Roux AF, Meunier I, Kalatzis V. USH2A variants causing retinitis pigmentosa or Usher syndrome provoke differential retinal phenotypes in disease-specific organoids. HGG ADVANCES 2023; 4:100229. [PMID: 37654703 PMCID: PMC10465966 DOI: 10.1016/j.xhgg.2023.100229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 08/03/2023] [Indexed: 09/02/2023] Open
Abstract
There is an emblematic clinical and genetic heterogeneity associated with inherited retinal diseases (IRDs). The most common form is retinitis pigmentosa (RP), a rod-cone dystrophy caused by pathogenic variants in over 80 different genes. Further complexifying diagnosis, different variants in individual RP genes can also alter the clinical phenotype. USH2A is the most prevalent gene for autosomal-recessive RP and one of the most challenging because of its large size and, hence, large number of variants. Moreover, USH2A variants give rise to non-syndromic and syndromic RP, known as Usher syndrome (USH) type 2, which is associated with vision and hearing loss. The lack of a clear genotype-phenotype correlation or prognostic models renders diagnosis highly challenging. We report here a long-awaited differential non-syndromic RP and USH phenotype in three human disease-specific models: fibroblasts, induced pluripotent stem cells (iPSCs), and mature iPSC-derived retinal organoids. Moreover, we identified distinct retinal phenotypes in organoids from multiple RP and USH individuals, which were validated by isogenic-corrected controls. Non-syndromic RP organoids showed compromised photoreceptor differentiation, whereas USH organoids showed a striking and unexpected cone phenotype. Furthermore, complementary clinical investigations identified macular atrophy in a high proportion of USH compared with RP individuals, further validating our observations that USH2A variants differentially affect cones. Overall, identification of distinct non-syndromic RP and USH phenotypes in multiple models provides valuable and robust readouts for testing the pathogenicity of USH2A variants as well as the efficacy of therapeutic approaches in complementary cell types.
Collapse
Affiliation(s)
- Carla Sanjurjo-Soriano
- Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM, Montpellier, France
| | - Carla Jimenez-Medina
- Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM, Montpellier, France
| | - Nejla Erkilic
- Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM, Montpellier, France
| | - Luisina Cappellino
- Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM, Montpellier, France
| | - Arnaud Lefevre
- National Reference Centre for Inherited Sensory Diseases, University of Montpellier, CHU, Montpellier, France
| | - Kerstin Nagel-Wolfrum
- Institute of Molecular Physiology, Molecular Cell Biology, and Photoreceptor Cell Biology, Johannes Gutenberg University Mainz, Mainz, Germany
- Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Uwe Wolfrum
- Institute of Molecular Physiology, Molecular Cell Biology, and Photoreceptor Cell Biology, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Erwin Van Wijk
- Department of Otorhinolaryngology, Hearing, & Genes, Radboud University Medical Center, Nijmegen, the Netherlands
- Donders Institute for Brain, Cognition, and Behavior, Nijmegen, the Netherlands
| | - Anne-Françoise Roux
- Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM, Montpellier, France
- Molecular Genetics Laboratory, University of Montpellier, CHU, Montpellier, France
| | - Isabelle Meunier
- Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM, Montpellier, France
- National Reference Centre for Inherited Sensory Diseases, University of Montpellier, CHU, Montpellier, France
| | - Vasiliki Kalatzis
- Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM, Montpellier, France
| |
Collapse
|
8
|
Torii K, Nishina S, Morikawa H, Mizobuchi K, Takayama M, Tachibana N, Kurata K, Hikoya A, Sato M, Nakano T, Fukami M, Azuma N, Hayashi T, Saitsu H, Hotta Y. The Structural Abnormalities Are Deeply Involved in the Cause of RPGRIP1-Related Retinal Dystrophy in Japanese Patients. Int J Mol Sci 2023; 24:13678. [PMID: 37761981 PMCID: PMC10531429 DOI: 10.3390/ijms241813678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 08/31/2023] [Accepted: 09/02/2023] [Indexed: 09/29/2023] Open
Abstract
Leber congenital amaurosis (LCA) is the most severe form of inherited retinal dystrophy. RPGRIP1-related LCA accounts for 5-6% of LCA. We performed whole-exome sequencing and whole-genome sequencing (WGS) on 29 patients with clinically suspected LCA and examined ophthalmic findings in patients with biallelic pathogenic variants of RPGRIP1. In addition to five previously reported cases, we identified five cases from four families with compound heterozygous RPGRIP1 variants using WGS. Five patients had null variants comprising frameshift variants, an Alu insertion, and microdeletions. A previously reported 1339 bp deletion involving exon 18 was found in four cases, and the deletion was relatively prevalent in the Japanese population (allele frequency: 0.002). Microdeletions involving exon 1 were detected in four cases. In patients with RPGRIP1 variants, visual acuity remained low, ranging from light perception to 0.2, and showed no correlation with age. In optical coherence tomography images, the ellipsoid zone (EZ) length decreased with age in all but one case of unimpaired EZ. The retinal structure was relatively preserved in all cases; however, there were cases with great differences in visual function compared to their siblings and a 56-year-old patient who still had a faint EZ line. Structural abnormalities may be important genetic causes of RPGRIP1-related retinal dystrophy in Japanese patients, and WGS was useful for detecting them.
Collapse
Affiliation(s)
- Kaoruko Torii
- Department of Ophthalmology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu 431-3192, Japan
| | - Sachiko Nishina
- Division of Ophthalmology, National Center for Child Health and Development, 2-10-1 Okura, Setagaya-ku, Tokyo 157-8535, Japan
| | - Hazuki Morikawa
- Division of Ophthalmology, National Center for Child Health and Development, 2-10-1 Okura, Setagaya-ku, Tokyo 157-8535, Japan
| | - Kei Mizobuchi
- Department of Ophthalmology, The Jikei University School of Medicine, 3-25-8 Nishi-shimbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Masakazu Takayama
- Department of Ophthalmology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu 431-3192, Japan
| | - Nobutaka Tachibana
- Department of Ophthalmology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu 431-3192, Japan
| | - Kentaro Kurata
- Department of Ophthalmology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu 431-3192, Japan
| | - Akiko Hikoya
- Department of Ophthalmology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu 431-3192, Japan
| | - Miho Sato
- Department of Ophthalmology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu 431-3192, Japan
| | - Tadashi Nakano
- Department of Ophthalmology, The Jikei University School of Medicine, 3-25-8 Nishi-shimbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Maki Fukami
- Department of Molecular Endocrinology, National Research Institute for Child Health and Development, 2-10-1 Okura, Setagaya-ku, Tokyo 157-8535, Japan
| | - Noriyuki Azuma
- Division of Ophthalmology, National Center for Child Health and Development, 2-10-1 Okura, Setagaya-ku, Tokyo 157-8535, Japan
- Department of Developmental and Regenerative Biology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Takaaki Hayashi
- Department of Ophthalmology, The Jikei University School of Medicine, 3-25-8 Nishi-shimbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Hirotomo Saitsu
- Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu 431-3192, Japan
| | - Yoshihiro Hotta
- Department of Ophthalmology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu 431-3192, Japan
| |
Collapse
|
9
|
Wang J, Li S, Jiang Y, Wang Y, Ouyang J, Yi Z, Sun W, Jia X, Xiao X, Wang P, Zhang Q. Pathogenic Variants in CEP290 or IQCB1 Cause Earlier-Onset Retinopathy in Senior-Loken Syndrome Compared to Those in INVS, NPHP3, or NPHP4. Am J Ophthalmol 2023; 252:188-204. [PMID: 36990420 DOI: 10.1016/j.ajo.2023.03.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 03/20/2023] [Accepted: 03/20/2023] [Indexed: 03/29/2023]
Abstract
PURPOSE Senior-Loken syndrome (SLSN) is an autosomal recessive disorder characterized by retinopathy and nephronophthisis. This study aimed to evaluate whether different phenotypes are associated with different variants or subsets of 10 SLSN-associated genes based on an in-house data set and a literature review. DESIGN Retrospective case series. METHODS Patients with biallelic variants in SLSN-associated genes, including NPHP1, INVS, NPHP3, NPHP4, IQCB1, CEP290, SDCCAG8, WDR19, CEP164, and TRAF3IP1, were recruited. Ocular phenotypes and nephrology medical records were collected for comprehensive analysis. RESULTS Variants in 5 genes were identified in 74 patients from 70 unrelated families, including CEP290 (61.4%), IQCB1 (28.6%), NPHP1 (4.2%), NPHP4 (2.9%), and WDR19 (2.9%). The median age at the onset of retinopathy was approximately 1 month (since birth). Nystagmus was the most common initial sign in patients with CEP290 (28 of 44, 63.6%) or IQCB1 (19 of 22, 86.4%) variants. Cone and rod responses were extinguished in 53 of 55 patients (96.4%). Characteristic fundus changes were observed in CEP290- and IQCB1-associated patients. During follow-up, 70 of the 74 patients were referred to nephrology, among whom nephronophthisis was not detected in 62 patients (88.6%) at a median age of 6 years but presented in 8 patients (11.4%) aged approximately 9 years. CONCLUSIONS Patients with pathogenic variants in CEP290 or IQCB1 presented early with retinopathy, whereas other patients with INVS, NPHP3, or NPHP4 variants first developed nephropathy. Therefore, awareness of the genetic and clinical features may facilitate the clinical management of SLSN, especially early intervention of kidney problems for patients with eyes affected first.
Collapse
Affiliation(s)
- Junwen Wang
- From the The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China
| | - Shiqiang Li
- From the The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China
| | - Yi Jiang
- From the The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China
| | - Yingwei Wang
- From the The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China
| | - Jiamin Ouyang
- From the The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China
| | - Zhen Yi
- From the The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China
| | - Wenmin Sun
- From the The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China
| | - Xiaoyun Jia
- From the The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China
| | - Xueshan Xiao
- From the The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China
| | - Panfeng Wang
- From the The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China
| | - Qingjiong Zhang
- From the The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China.
| |
Collapse
|
10
|
Wen S, Wang M, Qian X, Li Y, Wang K, Choi J, Pennesi ME, Yang P, Marra M, Koenekoop RK, Lopez I, Matynia A, Gorin M, Sui R, Yao F, Goetz K, Porto FBO, Chen R. Systematic assessment of the contribution of structural variants to inherited retinal diseases. Hum Mol Genet 2023; 32:2005-2015. [PMID: 36811936 PMCID: PMC10244226 DOI: 10.1093/hmg/ddad032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 01/03/2023] [Accepted: 02/11/2023] [Indexed: 02/24/2023] Open
Abstract
Despite increasing success in determining genetic diagnosis for patients with inherited retinal diseases (IRDs), mutations in about 30% of the IRD cases remain unclear or unsettled after targeted gene panel or whole exome sequencing. In this study, we aimed to investigate the contributions of structural variants (SVs) to settling the molecular diagnosis of IRD with whole-genome sequencing (WGS). A cohort of 755 IRD patients whose pathogenic mutations remain undefined were subjected to WGS. Four SV calling algorithms including include MANTA, DELLY, LUMPY and CNVnator were used to detect SVs throughout the genome. All SVs identified by any one of these four algorithms were included for further analysis. AnnotSV was used to annotate these SVs. SVs that overlap with known IRD-associated genes were examined with sequencing coverage, junction reads and discordant read pairs. Polymerase Chain Reaction (PCR) followed by Sanger sequencing was used to further confirm the SVs and identify the breakpoints. Segregation of the candidate pathogenic alleles with the disease was performed when possible. A total of 16 candidate pathogenic SVs were identified in 16 families, including deletions and inversions, representing 2.1% of patients with previously unsolved IRDs. Autosomal dominant, autosomal recessive and X-linked inheritance of disease-causing SVs were observed in 12 different genes. Among these, SVs in CLN3, EYS and PRPF31 were found in multiple families. Our study suggests that the contribution of SVs detected by short-read WGS is about 0.25% of our IRD patient cohort and is significantly lower than that of single nucleotide changes and small insertions and deletions.
Collapse
Affiliation(s)
- Shu Wen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Meng Wang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Xinye Qian
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Yumei Li
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Keqing Wang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jongsu Choi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Mark E Pennesi
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Paul Yang
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Molly Marra
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Robert K Koenekoop
- McGill Ocular Genetics Laboratory and Centre, Department of Paediatric Surgery, Human Genetics, and Ophthalmology, McGill University Health Centre, Montreal, Quebec, H4A 3S5, Canada
| | - Irma Lopez
- McGill Ocular Genetics Laboratory and Centre, Department of Paediatric Surgery, Human Genetics, and Ophthalmology, McGill University Health Centre, Montreal, Quebec, H4A 3S5, Canada
| | - Anna Matynia
- Jules Stein Eye Institute, Los Angeles, CA 90095, USA
- Ophthalmology, University of California Los Angeles David Geffen School of Medicine, Los Angeles, CA 90095, USA
| | - Michael Gorin
- Jules Stein Eye Institute, Los Angeles, CA 90095, USA
- Ophthalmology, University of California Los Angeles David Geffen School of Medicine, Los Angeles, CA 90095, USA
| | - Ruifang Sui
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100005, China
| | - Fengxia Yao
- Medical Research Center, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100005, China
| | - Kerry Goetz
- Office of the Director, National Eye Institute/National Institutes of Health, Bethesda, MD 20892, USA
| | - Fernanda Belga Ottoni Porto
- INRET Clínica e Centro de Pesquisa, Belo Horizonte, Minas Gerais, 30150270, Brazil
- Department of Ophthalmology, Santa Casa de Misericórdia de Belo Horizonte, Belo Horizonte, Minas Gerais, 30150221, Brazil
- Centro Oftalmológico de Minas Gerais, Belo Horizonte, Minas Gerais, 30180070, Brazil
| | - Rui Chen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| |
Collapse
|
11
|
Kocaaga A, Aköz İÖ, Demir NU, Paksoy B. Identification of novel variants in retinitis pigmentosa genes by whole-exome sequencing. REVISTA DA ASSOCIACAO MEDICA BRASILEIRA (1992) 2023; 69:e20221073. [PMID: 37222315 DOI: 10.1590/1806-9282.20221073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 02/23/2023] [Indexed: 05/25/2023]
Abstract
OBJECTIVE Retinitis pigmentosa is an inherited degenerative disorder causing severe retinal dystrophy and visual impairment, mainly with onset in the first or second decades. The next-generation sequencing has become an efficient tool to identify disease-causing mutations in retinitis pigmentosa. The aim of this retrospective study was to investigate novel gene variants and evaluate the utility of whole-exome sequencing in patients with retinitis pigmentosa. METHODS The medical records of 20 patients with retinitis pigmentosa at Eskişehir City Hospital between September 2019 and February 2022 were analyzed retrospectively. Peripheral venous blood was obtained, followed by the extraction of genomic DNAs. The medical and ophthalmic histories were collected, and ophthalmological examinations were performed. Whole-exome sequencing was performed to determine the genetic etiology of the patients. RESULTS The proportion of genetically solved cases was 75% (15/20) in the patients with retinitis pigmentosa. Molecular genetic testing identified 13 biallelic and 4 monoallelic mutations in known retinitis pigmentosa genes, including 11 novel variants. According to in silico prediction tools, nine variants were predicted as pathogenic or possibly pathogenic. We identified six previously reported mutations to be associated with retinitis pigmentosa. The age of onset of the patients ranged from 3 to 19, with a mean age of onset of 11.6. All patients had a loss of central vision. CONCLUSION As the first study of the application of whole-exome sequencing among patients with retinitis pigmentosa in a Turkish cohort, our results may contribute to the characterization of the spectrum of variants related to retinitis pigmentosa in the Turkish population. Future population-based studies will enable us to reveal the detailed genetic epidemiology of retinitis pigmentosa.
Collapse
Affiliation(s)
- Ayca Kocaaga
- Eskişehir City Hospital, Department of Medical Genetics - Eskişehir, Turkey
| | - İrem Öztürk Aköz
- Eskişehir City Hospital, Department of Ophthalmology - Eskişehir, Turkey
| | - Nihal Ulus Demir
- Eskişehir City Hospital, Department of Ophthalmology - Eskişehir, Turkey
| | - Bariş Paksoy
- Antalya Eğitim ve Araştırma Hastanesi, Department of Medical Genetics - Antalya, Turkey
| |
Collapse
|
12
|
Kim DG, Joo K, Han J, Choi M, Kim SW, Park KH, Park SJ, Lee CS, Byeon SH, Woo SJ. Genotypic Profile and Clinical Characteristics of CRX-Associated Retinopathy in Koreans. Genes (Basel) 2023; 14:genes14051057. [PMID: 37239417 DOI: 10.3390/genes14051057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 04/26/2023] [Accepted: 05/04/2023] [Indexed: 05/28/2023] Open
Abstract
This study aimed to investigate the clinical characteristics of Korean patients with retinal dystrophy associated with pathogenic variants of cone rod homeobox-containing gene (CRX). We retrospectively enrolled Korean patients with CRX-associated retinal dystrophy (CRX-RD) who visited two tertiary referral hospitals. Pathogenic variants were identified using targeted panel sequencing or whole-exome sequencing. We analyzed clinical features and phenotypic spectra according to genotype. Eleven patients with CRX-RD were included in this study. Six patients with cone-rod dystrophy (CORD), two with macular dystrophy (MD), two with Leber congenital amaurosis (LCA), and one with retinitis pigmentosa (RP) were included. One patient (9.1%) had autosomal recessive inheritance, and the other ten patients (90.9%) had autosomal dominant inheritance. Six patients (54.5%) were male, and the mean age of symptom onset was 27.0 ± 17.9 years. At the first presentation, the mean age was 39.4 ± 20.6 years, and best-corrected visual acuity (BCVA) (logMAR) was 0.76 ± 0.90 in the better eye. Negative electroretinography (ERG) was observed in seven (63.6%) patients. Nine pathogenic variants were identified, including two novel variants, c.101-1G>A and c.898T>C:p.(*300Glnext*118). Taken together with the variants reported in prior studies, all variants within the homeodomain are missense variants, whereas most variants downstream of the homeodomain are truncating variants (88%). The clinical features of pathogenic variants within the homeodomain are either CORD or MD with bull's eye maculopathy, whereas variants downstream of the homeodomain cause more diverse phenotypes, with CORD and MD in 36%, LCA in 40%, and RP in 24%. This is the first case series in Korea to investigate the CRX-RD genotype-phenotype correlation. Pathogenic variants downstream of the homeodomain of the CRX gene are present as RP, LCA, and CORD, whereas pathogenic variants within the homeodomain are mainly present as CORD or MD with bull's eye maculopathy. This trend was similar to previous genotype-phenotype analyses of CRX-RD. Further molecular biologic research on this correlation is required.
Collapse
Affiliation(s)
- Dong Geun Kim
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea
- Department of Ophthalmology, Inje University College of Medicine, Busan Paik Hospital, Busan 47392, Republic of Korea
| | - Kwangsic Joo
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea
| | - Jinu Han
- Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Severance Hospital, Seoul 06273, Republic of Korea
| | - Mihyun Choi
- Department of Ophthalmology, Guro Hospital, Korea University College of Medicine, Seoul 08308, Republic of Korea
| | - Seong-Woo Kim
- Department of Ophthalmology, Guro Hospital, Korea University College of Medicine, Seoul 08308, Republic of Korea
| | - Kyu Hyung Park
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea
| | - Sang Jun Park
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea
| | - Christopher Seungkyu Lee
- Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Severance Hospital, Seoul 06273, Republic of Korea
| | - Suk Ho Byeon
- Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Severance Hospital, Seoul 06273, Republic of Korea
| | - Se Joon Woo
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea
| |
Collapse
|
13
|
Retinitis Pigmentosa Associated with EYS Gene Mutations: Disease Severity Staging and Central Retina Atrophy. Diagnostics (Basel) 2023; 13:diagnostics13050850. [PMID: 36899994 PMCID: PMC10000790 DOI: 10.3390/diagnostics13050850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/07/2023] [Accepted: 02/13/2023] [Indexed: 02/25/2023] Open
Abstract
BACKGROUND Eyes shut homolog (EYS) gene mutations are estimated to affect at least 5% of patients with autosomal recessive retinitis pigmentosa. Since there is no mammalian model of human EYS disease, it is important to investigate its age-related changes and the degree of central retinal impairment. METHODS A cohort of EYS patients was studied. They underwent full ophthalmic examination as well as assessment of retinal function and structure, by full-field and focal electroretinograms (ERGs) and spectral domain optical coherence tomography (OCT), respectively. The disease severity stage was determined by the RP stage scoring system (RP-SSS). Central retina atrophy (CRA) was estimated from the automatically calculated area of the sub-retinal pigment epithelium (RPE) illumination (SRI). RESULTS The RP-SSS was positively correlated with age, showing an advanced severity score (≥8) at an age of 45 and a disease duration of 15 years. The RP-SSS was positively correlated with the CRA area. LogMAR visual acuity and ellipsoid zone width, but not ERG, were correlated with CRA. CONCLUSIONS In EYS-related disease, the RP-SSS showed advanced severity at a relative early age and was correlated with the central area of the RPE/photoreceptor atrophy. These correlations may be relevant in view of therapeutic interventions aimed at rescuing rods and cones in EYS-retinopathy.
Collapse
|
14
|
Hussain HMJ, Wang M, Huang A, Schmidt R, Qian X, Yang P, Marra M, Li Y, Pennesi ME, Chen R. Novel Pathogenic Mutations Identified from Whole-Genome Sequencing in Unsolved Cases of Patients Affected with Inherited Retinal Diseases. Genes (Basel) 2023; 14:447. [PMID: 36833373 PMCID: PMC9956865 DOI: 10.3390/genes14020447] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 01/31/2023] [Accepted: 02/03/2023] [Indexed: 02/12/2023] Open
Abstract
Inherited retinal diseases (IRDs) are a diverse set of visual disorders that collectively represent a major cause of early-onset blindness. With the reduction in sequencing costs in recent years, whole-genome sequencing (WGS) is being used more frequently, particularly when targeted gene panels and whole-exome sequencing (WES) fail to detect pathogenic mutations in patients. In this study, we performed mutation screens using WGS for a cohort of 311 IRD patients whose mutations were undetermined. A total of nine putative pathogenic mutations in six IRD patients were identified, including six novel mutations. Among them, four were deep intronic mutations that affected mRNA splicing, while the other five affected protein-coding sequences. Our results suggested that the rate of resolution of unsolved cases via targeted gene panels and WES can be further enhanced with WGS; however, the overall improvement may be limited.
Collapse
Affiliation(s)
- Hafiz Muhammad Jafar Hussain
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Meng Wang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Austin Huang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ryan Schmidt
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Xinye Qian
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Paul Yang
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Molly Marra
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Yumei Li
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Mark E. Pennesi
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Rui Chen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| |
Collapse
|
15
|
Poli FE, Yusuf IH, Clouston P, Shanks M, Whitfield J, Charbel Issa P, MacLaren RE. MERTK missense variants in three patients with retinitis pigmentosa. Ophthalmic Genet 2023; 44:74-82. [PMID: 36036427 PMCID: PMC9615558 DOI: 10.1080/13816810.2022.2113541] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 07/27/2022] [Accepted: 08/01/2022] [Indexed: 10/15/2022]
Abstract
BACKGROUND MERTK (MER proto-oncogene, tyrosine kinase) is a transmembrane protein essential in regulating photoreceptor outer segment phagocytosis. Biallelic mutations in MERTK cause retinal degeneration. Here we present the retinal phenotype of three patients with missense variants in MERTK. MATERIALS AND METHODS All patients underwent a full clinical examination, fundus photography, short-wavelength fundus autofluorescence and optical coherence tomography imaging. Two patients also underwent Goldmann visual field testing and electroretinography was undertaken for the third patient. Molecular genetic testing was undertaken using next generation or whole-exome sequencing with all variants confirmed by Sanger sequencing. RESULTS The first patient was a 29-year-old female heterozygous for a missense variant (c.1133C>T, p.Thr378 Met) and a nonsense variant (c.1744_1751delinsT, p.Ile582Ter) in MERTK. The second patient was a 26-year-old male homozygous for a c.2163T>A, p.His721Gln variant in MERTK. The third patient was an 11-year-old female heterozygous for a deletion of exons 5-19 and a missense variant (c.1866 G>C, p.Lys622Asn) in MERTK. Reduced night vision was the initial symptom in all patients. Fundoscopy revealed typical signs of retinitis pigmentosa (RP) with early-onset macular atrophy. All three MERTK missense variants affect highly conserved residues within functional domains, have low population frequencies and are predicted to be pathogenic in silico. CONCLUSIONS We report three missense variants in MERTK and present the associated phenotypic data, which are supportive of non-syndromic RP. MERTK is a promising candidate for viral-mediated gene replacement therapy. Moreover, one variant represents a single nucleotide transition, which is theoretically targetable with CRISPR-Cas9 base-editing.
Collapse
Affiliation(s)
- Federica E. Poli
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Imran H. Yusuf
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Penny Clouston
- Oxford Regional Genetics Laboratories, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Morag Shanks
- Oxford Regional Genetics Laboratories, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Jennifer Whitfield
- Oxford Regional Genetics Laboratories, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Peter Charbel Issa
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Robert E. MacLaren
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| |
Collapse
|
16
|
Wen S, Wang M, Qian X, Li Y, Wang K, Choi J, Pennesi ME, Yang P, Marra M, Koenekoop RK, Lopez I, Matynia A, Gorin M, Sui R, Yao F, Goetz K, Porto FBO, Chen R. Systematic assessment of the contribution of structural variants to inherited retinal diseases. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.02.522522. [PMID: 36789417 PMCID: PMC9928032 DOI: 10.1101/2023.01.02.522522] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Despite increasing success in determining genetic diagnosis for patients with inherited retinal diseases (IRDs), mutations in about 30% of the IRD cases remain unclear or unsettled after targeted gene panel or whole exome sequencing. In this study, we aimed to investigate the contributions of structural variants (SVs) to settling the molecular diagnosis of IRD with whole-genome sequencing (WGS). A cohort of 755 IRD patients whose pathogenic mutations remain undefined was subjected to WGS. Four SV calling algorithms including include MANTA, DELLY, LUMPY, and CNVnator were used to detect SVs throughout the genome. All SVs identified by any one of these four algorithms were included for further analysis. AnnotSV was used to annotate these SVs. SVs that overlap with known IRD-associated genes were examined with sequencing coverage, junction reads, and discordant read pairs. PCR followed by Sanger sequencing was used to further confirm the SVs and identify the breakpoints. Segregation of the candidate pathogenic alleles with the disease was performed when possible. In total, sixteen candidate pathogenic SVs were identified in sixteen families, including deletions and inversions, representing 2.1% of patients with previously unsolved IRDs. Autosomal dominant, autosomal recessive, and X-linked inheritance of disease-causing SVs were observed in 12 different genes. Among these, SVs in CLN3, EYS, PRPF31 were found in multiple families. Our study suggests that the contribution of SVs detected by short-read WGS is about 0.25% of our IRD patient cohort and is significantly lower than that of single nucleotide changes and small insertions and deletions.
Collapse
|
17
|
Lynn J, Raney A, Britton N, Ramoin J, Yang RW, Radojevic B, McClard CK, Kingsley R, Coussa RG, Bennett LD. Genetic Diagnosis for 64 Patients with Inherited Retinal Disease. Genes (Basel) 2022; 14:74. [PMID: 36672815 PMCID: PMC9859429 DOI: 10.3390/genes14010074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 12/07/2022] [Accepted: 12/23/2022] [Indexed: 12/28/2022] Open
Abstract
The overlapping genetic and clinical spectrum in inherited retinal degeneration (IRD) creates challenges for accurate diagnoses. The goal of this work was to determine the genetic diagnosis and clinical features for patients diagnosed with an IRD. After signing informed consent, peripheral blood or saliva was collected from 64 patients diagnosed with an IRD. Genetic testing was performed on each patient in a Clinical Laboratory Improvement Amendments of 1988 (CLIA) certified laboratory. Mutations were verified with Sanger sequencing and segregation analysis when possible. Visual acuity was measured with a traditional Snellen chart and converted to a logarithm of minimal angle of resolution (logMAR). Fundus images of dilated eyes were acquired with the Optos® camera (Dunfermline, UK). Horizontal line scans were obtained with spectral-domain optical coherence tomography (SDOCT; Spectralis, Heidelberg, Germany). Genetic testing combined with segregation analysis resolved molecular and clinical diagnoses for 75% of patients. Ten novel mutations were found and unique genotype phenotype associations were made for the genes RP2 and CEP83. Collective knowledge is thereby expanded of the genetic basis and phenotypic correlation in IRD.
Collapse
Affiliation(s)
- Jacob Lynn
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Austin Raney
- College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Nathaniel Britton
- College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Josh Ramoin
- College of Osteopathic Medicine, Oklahoma State University, Stillwater, OK 74078, USA
| | - Ryan W. Yang
- College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Bojana Radojevic
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
| | - Cynthia K. McClard
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
| | - Ronald Kingsley
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
| | - Razek Georges Coussa
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
| | - Lea D. Bennett
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
- College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
| |
Collapse
|
18
|
Hitti-Malin RJ, Dhaenens CM, Panneman DM, Corradi Z, Khan M, den Hollander AI, Farrar GJ, Gilissen C, Hoischen A, van de Vorst M, Bults F, Boonen EGM, Saunders P, Roosing S, Cremers FPM. Using single molecule Molecular Inversion Probes as a cost-effective, high-throughput sequencing approach to target all genes and loci associated with macular diseases. Hum Mutat 2022; 43:2234-2250. [PMID: 36259723 PMCID: PMC10092144 DOI: 10.1002/humu.24489] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 09/06/2022] [Accepted: 10/17/2022] [Indexed: 01/25/2023]
Abstract
Macular degenerations (MDs) are a subgroup of retinal disorders characterized by central vision loss. Knowledge is still lacking on the extent of genetic and nongenetic factors influencing inherited MD (iMD) and age-related MD (AMD) expression. Single molecule Molecular Inversion Probes (smMIPs) have proven effective in sequencing the ABCA4 gene in patients with Stargardt disease to identify associated coding and noncoding variation, however many MD patients still remain genetically unexplained. We hypothesized that the missing heritability of MDs may be revealed by smMIPs-based sequencing of all MD-associated genes and risk factors. Using 17,394 smMIPs, we sequenced the coding regions of 105 iMD and AMD-associated genes and noncoding or regulatory loci, known pseudo-exons, and the mitochondrial genome in two test cohorts that were previously screened for variants in ABCA4. Following detailed sequencing analysis of 110 probands, a diagnostic yield of 38% was observed. This established an ''MD-smMIPs panel," enabling a genotype-first approach in a high-throughput and cost-effective manner, whilst achieving uniform and high coverage across targets. Further analysis will identify known and novel variants in MD-associated genes to offer an accurate clinical diagnosis to patients. Furthermore, this will reveal new genetic associations for MD and potential genetic overlaps between iMD and AMD.
Collapse
Affiliation(s)
- Rebekkah J Hitti-Malin
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Claire-Marie Dhaenens
- Inserm, CHU Lille, U1172-LilNCog-Lille Neuroscience & Cognition, Univ. Lille, Lille, France
| | - Daan M Panneman
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Zelia Corradi
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Mubeen Khan
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Anneke I den Hollander
- Department of Ophthalmology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - G Jane Farrar
- The School of Genetics & Microbiology, The University of Dublin Trinity College, Dublin, Ireland
| | - Christian Gilissen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.,Radboud Institute of Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Alexander Hoischen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.,Radboud Institute of Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Internal Medicine, Radboud University Medical Center for Infectious Diseases (RCI), Radboud University Medical Center, Nijmegen, The Netherlands
| | - Maartje van de Vorst
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Femke Bults
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Erica G M Boonen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | | | | | - Susanne Roosing
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Frans P M Cremers
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| |
Collapse
|
19
|
Di Risi T, Cuomo M, Vinciguerra R, Ferraro S, Della Monica R, Costabile D, Buonaiuto M, Trio F, Capoluongo E, Visconti R, Riccio E, Pisani A, Chiariotti L. Methylome Profiling in Fabry Disease in Clinical Practice: A Proof of Concept. Int J Mol Sci 2022; 23:ijms232012110. [PMID: 36292965 PMCID: PMC9602470 DOI: 10.3390/ijms232012110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/04/2022] [Accepted: 10/07/2022] [Indexed: 11/16/2022] Open
Abstract
Anderson−Fabry disease (FD) is an X-linked disease caused by a functional deficit of the α-galactosidase A enzyme. FD diagnosis relies on the clinical manifestations and research of GLA gene mutations. However, because of the lack of a clear genotype/phenotype correlation, FD diagnosis can be challenging. Recently, several studies have highlighted the importance of investigating DNA methylation patterns for confirming the correct diagnosis of different rare Mendelian diseases, but to date, no such studies have been reported for FD. Thus, in the present investigation, we analyzed for the first time the genome-wide methylation profile of a well-characterized cohort of patients with Fabry disease. We profiled the methylation status of about 850,000 CpG sites in 5 FD patients, all carrying the same mutation in the GLA gene (exon 6 c.901C>G) and presenting comparable low levels of α-Gal A activity. We found that, although the whole methylome profile did not discriminate the FD group from the unaffected one, several genes were significantly differentially methylated in Fabry patients. Thus, we provide here a proof of concept, to be tested in patients with different mutations and in a larger cohort, that the methylation state of specific genes can potentially identify Fabry patients and possibly predict organ involvement and disease evolution.
Collapse
Affiliation(s)
- Teodolinda Di Risi
- CEINGE, Biotecnologie Avanzate, Via Gaetano Salvatore, 80145 Naples, Italy
- Department of Public Health, University Federico II, 80131 Naples, Italy
| | - Mariella Cuomo
- CEINGE, Biotecnologie Avanzate, Via Gaetano Salvatore, 80145 Naples, Italy
- Department of Molecular Medicine and Medical Biotechnologies, University Federico II, 80131 Naples, Italy
| | | | - Sara Ferraro
- CEINGE, Biotecnologie Avanzate, Via Gaetano Salvatore, 80145 Naples, Italy
| | - Rosa Della Monica
- CEINGE, Biotecnologie Avanzate, Via Gaetano Salvatore, 80145 Naples, Italy
- Department of Molecular Medicine and Medical Biotechnologies, University Federico II, 80131 Naples, Italy
| | - Davide Costabile
- CEINGE, Biotecnologie Avanzate, Via Gaetano Salvatore, 80145 Naples, Italy
- SEMM-European School of Molecular Medicine, University Federico II, 80145 Naples, Italy
| | - Michela Buonaiuto
- CEINGE, Biotecnologie Avanzate, Via Gaetano Salvatore, 80145 Naples, Italy
- Department of Molecular Medicine and Medical Biotechnologies, University Federico II, 80131 Naples, Italy
| | - Federica Trio
- CEINGE, Biotecnologie Avanzate, Via Gaetano Salvatore, 80145 Naples, Italy
| | - Ettore Capoluongo
- Department of Molecular Medicine and Medical Biotechnologies, University Federico II, 80131 Naples, Italy
- Department of Clinical Pathology and Genomics, Azienda Ospedaliera per L’Emergenza Cannizzaro, 95126 Catania, Italy
| | - Roberta Visconti
- CEINGE, Biotecnologie Avanzate, Via Gaetano Salvatore, 80145 Naples, Italy
- Institute for the Experimental Endocrinology and Oncology, Italian National Council of Research, 80131 Naples, Italy
| | - Eleonora Riccio
- Institute for Biomedical Research and Innovation, Italian National Research Council, 90146 Palermo, Italy
| | - Antonio Pisani
- Department of Public Health, University Federico II, 80131 Naples, Italy
| | - Lorenzo Chiariotti
- CEINGE, Biotecnologie Avanzate, Via Gaetano Salvatore, 80145 Naples, Italy
- Department of Molecular Medicine and Medical Biotechnologies, University Federico II, 80131 Naples, Italy
- Correspondence:
| |
Collapse
|
20
|
Daich Varela M, Bellingham J, Motta F, Jurkute N, Ellingford JM, Quinodoz M, Oprych K, Niblock M, Janeschitz-Kriegl L, Kaminska K, Cancellieri F, Scholl HPN, Lenassi E, Schiff E, Knight H, Black G, Rivolta C, Cheetham ME, Michaelides M, Mahroo OA, Moore AT, Webster AR, Arno G. Multidisciplinary team directed analysis of whole genome sequencing reveals pathogenic non-coding variants in molecularly undiagnosed inherited retinal dystrophies. Hum Mol Genet 2022; 32:595-607. [PMID: 36084042 PMCID: PMC9896476 DOI: 10.1093/hmg/ddac227] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 08/23/2022] [Accepted: 09/04/2022] [Indexed: 02/07/2023] Open
Abstract
The purpose of this paper is to identify likely pathogenic non-coding variants in inherited retinal dystrophy (IRD) genes, using genome sequencing (GS). Patients with IRD were recruited to the study and underwent comprehensive ophthalmological evaluation and GS. The results of GS were investigated through virtual gene panel analysis, and plausible pathogenic variants and clinical phenotype evaluated by the multidisciplinary team (MDT) discussion. For unsolved patients in whom a specific gene was suspected to harbor a missed pathogenic variant, targeted re-analysis of non-coding regions was performed on GS data. Candidate variants were functionally tested by messenger RNA analysis, minigene or luciferase reporter assays. Previously unreported, likely pathogenic, non-coding variants in 7 genes (PRPF31, NDP, IFT140, CRB1, USH2A, BBS10 and GUCY2D), were identified in 11 patients. These were shown to lead to mis-splicing (PRPF31, IFT140, CRB1 and USH2A) or altered transcription levels (BBS10 and GUCY2D). MDT-led, phenotype-driven, non-coding variant re-analysis of GS is effective in identifying the missing causative alleles.
Collapse
Affiliation(s)
- Malena Daich Varela
- UCL Institute of Ophthalmology, London EC1V 9EL, UK,Moorfields Eye Hospital, London EC1V 2PD, UK
| | | | - Fabiana Motta
- UCL Institute of Ophthalmology, London EC1V 9EL, UK,Department of Ophthalmology, Universidade Federal de Sao Paulo, Sao Paulo 04021001, Brazil
| | - Neringa Jurkute
- UCL Institute of Ophthalmology, London EC1V 9EL, UK,Moorfields Eye Hospital, London EC1V 2PD, UK
| | - Jamie M Ellingford
- North West Genomic Laboratory Hub, Manchester Centre for Genomic Medicine, Manchester University Hospitals NHS Foundation Trust, St Mary’s Hospital, Manchester M13 9WL, UK,Division of Evolution and Genomic Sciences, Neuroscience and Mental Health Domain, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, UK
| | - Mathieu Quinodoz
- Institute of Molecular and Clinical Ophthalmology Basel, Basel 4031, Switzerland,Department of Ophthalmology, University of Basel, Basel 4031, Switzerland,Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK
| | | | | | - Lucas Janeschitz-Kriegl
- Institute of Molecular and Clinical Ophthalmology Basel, Basel 4031, Switzerland,Department of Ophthalmology, University of Basel, Basel 4031, Switzerland
| | - Karolina Kaminska
- Institute of Molecular and Clinical Ophthalmology Basel, Basel 4031, Switzerland,Department of Ophthalmology, University of Basel, Basel 4031, Switzerland
| | - Francesca Cancellieri
- Institute of Molecular and Clinical Ophthalmology Basel, Basel 4031, Switzerland,Department of Ophthalmology, University of Basel, Basel 4031, Switzerland
| | - Hendrik P N Scholl
- Institute of Molecular and Clinical Ophthalmology Basel, Basel 4031, Switzerland,Department of Ophthalmology, University of Basel, Basel 4031, Switzerland
| | - Eva Lenassi
- North West Genomic Laboratory Hub, Manchester Centre for Genomic Medicine, Manchester University Hospitals NHS Foundation Trust, St Mary’s Hospital, Manchester M13 9WL, UK,Division of Evolution and Genomic Sciences, Neuroscience and Mental Health Domain, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, UK
| | | | | | - Graeme Black
- North West Genomic Laboratory Hub, Manchester Centre for Genomic Medicine, Manchester University Hospitals NHS Foundation Trust, St Mary’s Hospital, Manchester M13 9WL, UK,Division of Evolution and Genomic Sciences, Neuroscience and Mental Health Domain, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, UK
| | - Carlo Rivolta
- Institute of Molecular and Clinical Ophthalmology Basel, Basel 4031, Switzerland,Department of Ophthalmology, University of Basel, Basel 4031, Switzerland,Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK
| | | | - Michel Michaelides
- UCL Institute of Ophthalmology, London EC1V 9EL, UK,Moorfields Eye Hospital, London EC1V 2PD, UK
| | - Omar A Mahroo
- UCL Institute of Ophthalmology, London EC1V 9EL, UK,Moorfields Eye Hospital, London EC1V 2PD, UK
| | - Anthony T Moore
- UCL Institute of Ophthalmology, London EC1V 9EL, UK,Moorfields Eye Hospital, London EC1V 2PD, UK,University of California, San Francisco, CA 94607, USA
| | - Andrew R Webster
- UCL Institute of Ophthalmology, London EC1V 9EL, UK,Moorfields Eye Hospital, London EC1V 2PD, UK
| | - Gavin Arno
- To whom correspondence should be addressed at: UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1 9EL, UK. Tel: +44 2076086971;
| |
Collapse
|
21
|
Wang J, Wang Y, Jiang Y, Li X, Xiao X, Li S, Jia X, Sun W, Wang P, Zhang Q. Autosomal Dominant Retinitis Pigmentosa-Associated TOPORS Protein Truncating Variants Are Exclusively Located in the Region of Amino Acid Residues 807 to 867. Invest Ophthalmol Vis Sci 2022; 63:19. [PMID: 35579903 PMCID: PMC9123486 DOI: 10.1167/iovs.63.5.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Heterozygous truncating variants of TOPORS have been reported to cause autosomal dominant retinitis pigmentosa (adRP). The purpose of this study was to investigate whether all heterozygous truncating variants, including copy number variants (CNVs), are pathogenic. Methods TOPORS truncating variants were collected and reviewed through an in-house dataset and existing databases. Individuals with truncating variants underwent ophthalmological evaluation. Results Six truncating variants were detected in seven families. Three N-terminus truncating variants were detected in three families without RP, and the other three were identified in four unrelated families with typical RP. Based on the in-house dataset and published literature, 17 truncating variants were identified in 47 families with RP. All RP-associated truncating alleles, except one, were distributed in the last exon of TOPORS and clustered in amino acid residues 807 to 867 (46/47, 97.9%). Conversely, in the gnomAD database, only one truncating allele (1/27, 3.7%) was in this region, and the others were outside (26/27, 96.3%), suggesting that the pathogenic truncating variants were significantly clustered in residues 807 to 867 (χ2 = 65.6, P = 1.1 × 10–17). Additionally, three CNVs involving the N-terminus of TOPORS were recorded in control populations but were absent in affected patients. Conclusions This study suggests that all pathogenic truncating variants of TOPORS were clustered in residues 807 to 867, whereas the truncating variants outside this region and the CNVs involving the N-terminus were not associated with RP. A dominant-negative effect, rather than haploinsufficiency, is speculated to be the underlying pathogenesis. These findings provide valuable information for interpreting variation in TOPORS and other genes in similar situations, especially for CNVs.
Collapse
Affiliation(s)
- Junwen Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Yingwei Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Yi Jiang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xueqing Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xueshan Xiao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Shiqiang Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xiaoyun Jia
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Wenmin Sun
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Panfeng Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Qingjiong Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| |
Collapse
|
22
|
Occelli LM, Daruwalla A, De Silva SR, Winkler PA, Sun K, Pasmanter N, Minella A, Querubin J, Lyons LA, Robson AG, Heon E, Michaelides M, Webster AR, Palczewski K, Vincent A, Mahroo OA, Kiser PD, Petersen-Jones SM. A large animal model of RDH5-associated retinopathy recapitulates important features of the human phenotype. Hum Mol Genet 2022; 31:1263-1277. [PMID: 34726233 PMCID: PMC9029234 DOI: 10.1093/hmg/ddab316] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 10/22/2021] [Accepted: 10/25/2021] [Indexed: 11/12/2022] Open
Abstract
Pathogenic variants in retinol dehydrogenase 5 (RDH5) attenuate supply of 11-cis-retinal to photoreceptors leading to a range of clinical phenotypes including night blindness because of markedly slowed rod dark adaptation and in some patients, macular atrophy. Current animal models (such as Rdh5-/- mice) fail to recapitulate the functional or degenerative phenotype. Addressing this need for a relevant animal model we present a new domestic cat model with a loss-of-function missense mutation in RDH5 (c.542G > T; p.Gly181Val). As with patients, affected cats have a marked delay in recovery of dark adaptation. In addition, the cats develop a degeneration of the area centralis (equivalent to the human macula). This recapitulates the development of macular atrophy that is reported in a subset of patients with RDH5 mutations and is shown in this paper in seven patients with biallelic RDH5 mutations. There is notable variability in the age at onset of the area centralis changes in the cat, with most developing changes as juveniles but some not showing changes over the first few years of age. There is similar variability in development of macular atrophy in patients and while age is a risk factor, it is hypothesized that genetic modifying loci influence disease severity, and we suspect the same is true in the cat model. This novel cat model provides opportunities to improve molecular understanding of macular atrophy and test therapeutic interventions for RDH5-associated retinopathies.
Collapse
Affiliation(s)
- Laurence M Occelli
- Department of Small Animal Clinical Sciences, Michigan State University, East Lansing. MI 48824, USA
| | - Anahita Daruwalla
- Department of Physiology & Biophysics, University of California, Irvine School of Medicine, Irvine, CA 92697, USA
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Samantha R De Silva
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- UCL Institute of Ophthalmology, University College, London, UK
| | - Paige A Winkler
- Department of Small Animal Clinical Sciences, Michigan State University, East Lansing. MI 48824, USA
| | - Kelian Sun
- Department of Small Animal Clinical Sciences, Michigan State University, East Lansing. MI 48824, USA
| | - Nathaniel Pasmanter
- Department of Small Animal Clinical Sciences, Michigan State University, East Lansing. MI 48824, USA
| | - Andrea Minella
- Department of Small Animal Clinical Sciences, Michigan State University, East Lansing. MI 48824, USA
| | - Janice Querubin
- Department of Small Animal Clinical Sciences, Michigan State University, East Lansing. MI 48824, USA
| | - Leslie A Lyons
- Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | | | - Anthony G Robson
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- UCL Institute of Ophthalmology, University College, London, UK
| | - Elise Heon
- Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Canada
- Institute of Medical Science, The University of Toronto, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada
| | - Michel Michaelides
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- UCL Institute of Ophthalmology, University College, London, UK
| | - Andrew R Webster
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- UCL Institute of Ophthalmology, University College, London, UK
| | - Krzysztof Palczewski
- Department of Physiology & Biophysics, University of California, Irvine School of Medicine, Irvine, CA 92697, USA
- Department of Ophthalmology, Gavin Herbert Eye Institute, Center for Translational Vision Research, University of California, Irvine, CA 92617, USA
- The Department of Chemistry, Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697, USA
| | - Ajoy Vincent
- Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Canada
- Institute of Medical Science, The University of Toronto, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada
| | - Omar A Mahroo
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- UCL Institute of Ophthalmology, University College, London, UK
- Section of Ophthalmology, King’s College London, St Thomas’ Hospital Campus, London, UK
- Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Philip D Kiser
- Department of Physiology & Biophysics, University of California, Irvine School of Medicine, Irvine, CA 92697, USA
- Department of Ophthalmology, Gavin Herbert Eye Institute, Center for Translational Vision Research, University of California, Irvine, CA 92617, USA
- Research Service, The Veterans Affairs Long Beach Health Care System, Long Beach, CA 90822, USA
| | - Simon M Petersen-Jones
- Department of Small Animal Clinical Sciences, Michigan State University, East Lansing. MI 48824, USA
| |
Collapse
|
23
|
He K, Zhou Y, Li N. Mutations of TOPORS identified in families with retinitis pigmentosa. Ophthalmic Genet 2022; 43:371-377. [PMID: 35254173 DOI: 10.1080/13816810.2022.2039721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Kaiwen He
- Department of Ophthalmology, Key Laboratory of Major Diseases in Children, Ministry of Education, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, China 100045
| | - Yunyu Zhou
- Department of Ophthalmology, Key Laboratory of Major Diseases in Children, Ministry of Education, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, China 100045
| | - Ningdong Li
- Department of Ophthalmology, Key Laboratory of Major Diseases in Children, Ministry of Education, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, China 100045
| |
Collapse
|
24
|
Sallum JMF, Kaur VP, Shaikh J, Banhazi J, Spera C, Aouadj C, Viriato D, Fischer MD. Epidemiology of Mutations in the 65-kDa Retinal Pigment Epithelium (RPE65) Gene-Mediated Inherited Retinal Dystrophies: A Systematic Literature Review. Adv Ther 2022; 39:1179-1198. [PMID: 35098484 PMCID: PMC8918161 DOI: 10.1007/s12325-021-02036-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 12/22/2021] [Indexed: 12/26/2022]
Abstract
INTRODUCTION Inherited retinal dystrophies (IRDs) represent a genetically diverse group of progressive, visually debilitating diseases. Adult and paediatric patients with vision loss due to IRD caused by biallelic mutations in the 65-kDa retinal pigment epithelium (RPE65) gene are often clinically diagnosed as retinitis pigmentosa (RP), and Leber congenital amaurosis (LCA). This study aimed to understand the epidemiological landscape of RPE65 gene-mediated IRD through a systematic review of the literature, as the current evidence base for its epidemiology is very limited. METHODS Medline, Embase, and other databases were searched for articles on the epidemiology of RPE65 gene-mediated IRDs from inception until June 2021. Studies were included if they were original research articles reporting the epidemiology of RP and LCA and/or proportion of RPE65 gene mutations in these clinically diagnosed or molecularly confirmed IRDs patients. RESULTS A total of 100 studies with relevant data were included in this systematic review. The range for prevalence of LCA and RP in the literature was 1.20-2.37 and 11.09-26.43 per 100,000, respectively. The proportion of RPE65 mutations in clinically diagnosed patients with LCA was found to be between ~ 2-16% within the US and major European countries (France, Germany, Italy, Spain, and the UK). This range was also comparable to our findings in the Asian region for RPE65-LCA (1.26-16.67%). Similarly, for these European countries, RPE65-RP was estimated between 0.23 and 1.94%, and RPE65-IRD range was 1.2-14%. Further, in the Americas region, mutations in RPE65 were reported to cause 1-3% of RP and 0.8-3.7% of IRD cases. Lastly, the RPE65-IRD range was 4.81-8% in the Middle East region. CONCLUSIONS There are significant variations in reporting of RPE65 proportions within countries as well as regions. Generating robust epidemiological evidence on RPE65 gene-mediated IRDs would be fundamental to support rare disease awareness, timely therapeutic intervention, and public health decision-making.
Collapse
Affiliation(s)
- Juliana M F Sallum
- Department of Ophthalmology, Universidade Federal de São Paulo, São Paulo, Brazil
- Instituto de Genética Ocular, São Paulo, Brazil
| | | | | | | | | | | | | | - M Dominik Fischer
- Centre for Ophthalmology, University Eye Hospital, University Hospital Tübingen, Tübingen, Germany
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| |
Collapse
|
25
|
Lee JK, Kwon WK, Hong SN, Chang DK, Kim HC, Jang JH, Kim JW. Necessity of Multiplex Ligation Probe Amplification in Genetic Tests: Germline variant analysis of the APC gene in familial adenomatous polyposis patients. Cancer Genet 2022; 262-263:95-101. [DOI: 10.1016/j.cancergen.2022.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 01/10/2022] [Accepted: 02/09/2022] [Indexed: 11/02/2022]
|
26
|
Levy MA, McConkey H, Kerkhof J, Barat-Houari M, Bargiacchi S, Biamino E, Bralo MP, Cappuccio G, Ciolfi A, Clarke A, DuPont BR, Elting MW, Faivre L, Fee T, Fletcher RS, Cherik F, Foroutan A, Friez MJ, Gervasini C, Haghshenas S, Hilton BA, Jenkins Z, Kaur S, Lewis S, Louie RJ, Maitz S, Milani D, Morgan AT, Oegema R, Østergaard E, Pallares NR, Piccione M, Pizzi S, Plomp AS, Poulton C, Reilly J, Relator R, Rius R, Robertson S, Rooney K, Rousseau J, Santen GWE, Santos-Simarro F, Schijns J, Squeo GM, St John M, Thauvin-Robinet C, Traficante G, van der Sluijs PJ, Vergano SA, Vos N, Walden KK, Azmanov D, Balci T, Banka S, Gecz J, Henneman P, Lee JA, Mannens MMAM, Roscioli T, Siu V, Amor DJ, Baynam G, Bend EG, Boycott K, Brunetti-Pierri N, Campeau PM, Christodoulou J, Dyment D, Esber N, Fahrner JA, Fleming MD, Genevieve D, Kerrnohan KD, McNeill A, Menke LA, Merla G, Prontera P, Rockman-Greenberg C, Schwartz C, Skinner SA, Stevenson RE, Vitobello A, Tartaglia M, Alders M, Tedder ML, Sadikovic B. Novel diagnostic DNA methylation episignatures expand and refine the epigenetic landscapes of Mendelian disorders. HGG ADVANCES 2022; 3:100075. [PMID: 35047860 PMCID: PMC8756545 DOI: 10.1016/j.xhgg.2021.100075] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 11/30/2021] [Indexed: 02/07/2023] Open
Abstract
Overlapping clinical phenotypes and an expanding breadth and complexity of genomic associations are a growing challenge in the diagnosis and clinical management of Mendelian disorders. The functional consequences and clinical impacts of genomic variation may involve unique, disorder-specific, genomic DNA methylation episignatures. In this study, we describe 19 novel episignature disorders and compare the findings alongside 38 previously established episignatures for a total of 57 episignatures associated with 65 genetic syndromes. We demonstrate increasing resolution and specificity ranging from protein complex, gene, sub-gene, protein domain, and even single nucleotide-level Mendelian episignatures. We show the power of multiclass modeling to develop highly accurate and disease-specific diagnostic classifiers. This study significantly expands the number and spectrum of disorders with detectable DNA methylation episignatures, improves the clinical diagnostic capabilities through the resolution of unsolved cases and the reclassification of variants of unknown clinical significance, and provides further insight into the molecular etiology of Mendelian conditions.
Collapse
Affiliation(s)
- Michael A Levy
- Verspeeten Clinical Genome Centre; London Health Sciences Centre, London, ON N6A 5W9, Canada
| | - Haley McConkey
- Verspeeten Clinical Genome Centre; London Health Sciences Centre, London, ON N6A 5W9, Canada
| | - Jennifer Kerkhof
- Verspeeten Clinical Genome Centre; London Health Sciences Centre, London, ON N6A 5W9, Canada
| | - Mouna Barat-Houari
- Autoinflammatory and Rare Diseases Unit, Medical Genetic Department for Rare Diseases and Personalized Medicine, CHU Montpellier, Montpellier, France
| | - Sara Bargiacchi
- Medical Genetics Unit, "A. Meyer" Children's Hospital of Florence, Florence, Italy
| | - Elisa Biamino
- Department of Pediatrics, University of Turin, Turin, Italy
| | - María Palomares Bralo
- Institute of Medical and Molecular Genetics (INGEMM), Hospital Universitario La Paz, IdiPAZ, CIBERER, ISCIII, Madrid, Spain
| | - Gerarda Cappuccio
- Department of Translational Medicine, Federico II University of Naples, Naples, Italy.,Telethon Institute of Genetics and Medicine, Pozzuoli, Italy
| | - Andrea Ciolfi
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy
| | - Angus Clarke
- Cardiff University School of Medicine, Cardiff, UK
| | | | - Mariet W Elting
- Department of Clinical Genetics, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Laurence Faivre
- INSERM-Université de Bourgogne UMR1231 GAD « Génétique Des Anomalies du Développement », FHU-TRANSLAD, UFR Des Sciences de Santé, Dijon, France.,Centre de Référence Maladies Rares «Anomalies du Développement et Syndromes Malformatifs », Centre de Génétique, FHU-TRANSLAD, CHU Dijon Bourgogne, Dijon, France
| | - Timothy Fee
- Greenwood Genetic Center, Greenwood, SC 29646, USA
| | | | - Florian Cherik
- Genetic medical center, CHU Clermont Ferrand, France.,Montpellier University, Reference Center for Rare Disease, Medical Genetic Department for Rare Disease and Personalize Medicine, Inserm Unit 1183, CHU Montpellier, Montpellier, France
| | - Aidin Foroutan
- Department of Pathology and Laboratory Medicine, Western University, London, ON N6A 3K7, Canada
| | | | - Cristina Gervasini
- Division of Medical Genetics, Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
| | - Sadegheh Haghshenas
- Department of Pathology and Laboratory Medicine, Western University, London, ON N6A 3K7, Canada
| | | | - Zandra Jenkins
- Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Simranpreet Kaur
- Brain and Mitochondrial Research Group, Murdoch Children's Research Institute and Department of Paediatrics, University of Melbourne, Melbourne, Australia
| | - Suzanne Lewis
- BC Children's and Women's Hospital and Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, Canada
| | | | - Silvia Maitz
- Clinical Pediatric Genetics Unit, Pediatrics Clinics, MBBM Foundation, Hospital San Gerardo, Monza, Italy
| | - Donatella Milani
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Angela T Morgan
- Murdoch Children's Research Institute and Department of Paediatrics, University of Melbourne, Melbourne, Australia
| | - Renske Oegema
- Department of Genetics, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Elsebet Østergaard
- Department of Clinical Genetics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.,Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Nathalie Ruiz Pallares
- Autoinflammatory and Rare Diseases Unit, Medical Genetic Department for Rare Diseases and Personalized Medicine, CHU Montpellier, Montpellier, France
| | - Maria Piccione
- Medical Genetics Unit Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties, University of Palermo, Palermo, Italy
| | - Simone Pizzi
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy
| | - Astrid S Plomp
- Amsterdam UMC, University of Amsterdam, Department of Human Genetics, Amsterdam Reproduction and Development Research Institute, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands
| | - Cathryn Poulton
- Undiagnosed Diseases Program, Genetic Services of Western Australia, King Edward Memorial Hospital, Perth, Australia
| | - Jack Reilly
- Department of Pathology and Laboratory Medicine, Western University, London, ON N6A 3K7, Canada
| | - Raissa Relator
- Verspeeten Clinical Genome Centre; London Health Sciences Centre, London, ON N6A 5W9, Canada
| | - Rocio Rius
- Brain and Mitochondrial Research Group, Murdoch Children's Research Institute, Melbourne, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Australia
| | - Stephen Robertson
- Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Kathleen Rooney
- Verspeeten Clinical Genome Centre; London Health Sciences Centre, London, ON N6A 5W9, Canada.,Department of Pathology and Laboratory Medicine, Western University, London, ON N6A 3K7, Canada
| | - Justine Rousseau
- CHU Sainte-Justine Research Center, University of Montreal, Montreal, QC H3T 1C5, Canada
| | - Gijs W E Santen
- Department of Clinical Genetics, LUMC, Leiden, the Netherlands
| | - Fernando Santos-Simarro
- Institute of Medical and Molecular Genetics (INGEMM), Hospital Universitario La Paz, IdiPAZ, CIBERER, ISCIII, Madrid, Spain
| | - Josephine Schijns
- Department of Pediatrics, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Gabriella Maria Squeo
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy
| | - Miya St John
- Murdoch Children's Research Institute and Department of Paediatrics, University of Melbourne, Melbourne, Australia
| | - Christel Thauvin-Robinet
- INSERM-Université de Bourgogne UMR1231 GAD « Génétique Des Anomalies du Développement », FHU-TRANSLAD, UFR Des Sciences de Santé, Dijon, France.,Centre de Référence Maladies Rares «Anomalies du Développement et Syndromes Malformatifs », Centre de Génétique, FHU-TRANSLAD, CHU Dijon Bourgogne, Dijon, France.,Unité Fonctionnelle d'Innovation Diagnostique des Maladies Rares, FHU-TRANSLAD, France Hospitalo-Universitaire Médecine Translationnelle et Anomalies du Développement (TRANSLAD), Centre Hospitalier Universitaire Dijon Bourgogne, CHU Dijon Bourgogne, Dijon, France.,Centre de Référence Déficiences Intellectuelles de Causes Rares, Hôpital D'Enfants, CHU Dijon Bourgogne, 21000 Dijon, France
| | - Giovanna Traficante
- Medical Genetics Unit, "A. Meyer" Children's Hospital of Florence, Florence, Italy
| | | | - Samantha A Vergano
- Division of Medical Genetics and Metabolism, Children's Hospital of The King's Daughters, Norfolk, VA, USA.,Department of Pediatrics, Eastern Virginia Medical School, Norfolk, VA, USA
| | - Niels Vos
- Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Amsterdam Reproduction and Development Research Institute, Meibergdreef 9, Amsterdam, the Netherlands
| | | | - Dimitar Azmanov
- Department of Diagnostic Genomics, PathWest Laboratory Medicine, QEII Medical Centre, Perth, Australia
| | - Tugce Balci
- Department of Pediatrics, Division of Medical Genetics, Western University, London, ON N6A 3K7, Canada.,Medical Genetics Program of Southwestern Ontario, London Health Sciences Centre and Children's Health Research Institute, London, ON N6A5W9, Canada
| | - Siddharth Banka
- Division of Evolution, Infection & Genomics, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK.,Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University NHS Foundation Trust, Health Innovation Manchester, Manchester, UK
| | - Jozef Gecz
- School of Medicine, Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia.,South Australian Health and Medical Research Institute, Adelaide, SA 5005, Australia
| | - Peter Henneman
- Amsterdam UMC, University of Amsterdam, Department of Human Genetics, Amsterdam Reproduction and Development Research Institute, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands
| | | | - Marcel M A M Mannens
- Amsterdam UMC, University of Amsterdam, Department of Human Genetics, Amsterdam Reproduction and Development Research Institute, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands
| | - Tony Roscioli
- Neuroscience Research Australia (NeuRA), Sydney, Australia.,Prince of Wales Clinical School, Faculty of Medicine, University of New South Wales, Sydney, Australia.,New South Wales Health Pathology Randwick Genomics, Prince of Wales Hospital, Sydney, Australia.,Centre for Clinical Genetics, Sydney Children's Hospital, Sydney, Australia
| | - Victoria Siu
- Department of Pediatrics, Division of Medical Genetics, Western University, London, ON N6A 3K7, Canada.,Medical Genetics Program of Southwestern Ontario, London Health Sciences Centre and Children's Health Research Institute, London, ON N6A5W9, Canada
| | - David J Amor
- Murdoch Children's Research Institute and Department of Paediatrics, University of Melbourne, Melbourne, Australia
| | - Gareth Baynam
- Undiagnosed Diseases Program, Genetic Services of Western Australia, King Edward Memorial Hospital, Perth, Australia.,Undiagnosed Diseases Program, Genetic Services of Western Australia, King Edward Memorial Hospital, Perth, Australia.,Division of Paediatrics and Telethon Kids Institute, Faculty of Health and Medical Sciences, Perth, Australia
| | | | - Kym Boycott
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, ON, Canada.,Department of Genetics, Children's Hospital of Eastern Ontario, Ottawa, ON, Canada
| | - Nicola Brunetti-Pierri
- Department of Translational Medicine, Federico II University of Naples, Naples, Italy.,Telethon Institute of Genetics and Medicine, Pozzuoli, Italy
| | - Philippe M Campeau
- CHU Sainte-Justine Research Center, University of Montreal, Montreal, QC H3T 1C5, Canada
| | - John Christodoulou
- Brain and Mitochondrial Research Group, Murdoch Children's Research Institute and Department of Paediatrics, University of Melbourne, Melbourne, Australia
| | - David Dyment
- Children's Hospital of Eastern Ontario, Ottawa, Canada
| | | | - Jill A Fahrner
- Departments of Genetic Medicine and Pediatrics, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Mark D Fleming
- Department of Pathology, Boston Children's Hospital, Boston, MA, USA
| | - David Genevieve
- Montpellier University, Reference Center for Rare Disease, Medical Genetic Department for Rare Disease and Personalize Medicine, Inserm Unit 1183, CHU Montpellier, Montpellier, France
| | - Kristin D Kerrnohan
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, ON, Canada.,Newborn Screening Ontario, Children's Hospital of Eastern Ontario, Ottawa, Canada
| | - Alisdair McNeill
- Department of Neuroscience, University of Sheffield, Sheffield Children's Hospital NHS Foundation Trust, Sheffield, UK
| | - Leonie A Menke
- Department of Pediatrics, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Giuseppe Merla
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy.,Laboratory of Regulatory and Functional Genomics, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo (Foggia), Italy
| | - Paolo Prontera
- Medical Genetics Unit, University of Perugia Hospital SM della Misericordia, Perugia, Italy
| | - Cheryl Rockman-Greenberg
- Department of Pediatrics and Child Health, Rady Faculty of Health Sciences, University of Manitoba and Program in Genetics and Metabolism, Shared Health MB, Winnipeg, MB, Canada
| | | | | | | | - Antonio Vitobello
- INSERM-Université de Bourgogne UMR1231 GAD « Génétique Des Anomalies du Développement », FHU-TRANSLAD, UFR Des Sciences de Santé, Dijon, France.,Unité Fonctionnelle d'Innovation Diagnostique des Maladies Rares, FHU-TRANSLAD, France Hospitalo-Universitaire Médecine Translationnelle et Anomalies du Développement (TRANSLAD), Centre Hospitalier Universitaire Dijon Bourgogne, CHU Dijon Bourgogne, Dijon, France
| | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy
| | - Marielle Alders
- Amsterdam UMC, University of Amsterdam, Department of Human Genetics, Amsterdam Reproduction and Development Research Institute, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands
| | | | - Bekim Sadikovic
- Verspeeten Clinical Genome Centre; London Health Sciences Centre, London, ON N6A 5W9, Canada.,Department of Pathology and Laboratory Medicine, Western University, London, ON N6A 3K7, Canada
| |
Collapse
|
27
|
Ghaffari SR, Rafati M, Shadnoush M, Pourbabaee S, Aghighi M, Samiee SM, Kermanchi J, Alaei MR, Salehpour S, Amirkashani D, Setoodeh A, Sarkhail P, Badv RS, Aminzadeh M, Shiva S, Eshraghi P, Moravej H, Hashemipour M, Rostampour N, Hamidieh AA, Shamsian BS, Shams S, Zamanfar D, Ebrahimi A, Otadi A, Tara SZ, Barati Z, Fakhri L, Hoseini A, Amiri H, Ramandi S, Mostofinezhad N, Kani ZP, Mohammadyari E, Khosravi M, Saadati M, Hoseininasab F, Khorshid HRK, Modaberisaber Y. Molecular characterization of a large cohort of Mucopolysaccharidosis patients: Iran Mucopolysaccharidosis RE-diagnosis Study (IMPRESsion). Hum Mutat 2022; 43:e1-e23. [PMID: 35005816 DOI: 10.1002/humu.24328] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 12/03/2021] [Accepted: 01/05/2022] [Indexed: 01/30/2023]
Abstract
Mucopolysaccharidoses (MPSs) are rare, heterogeneous inborn errors of metabolism (IEM) diagnosed through a combination of clinical, biochemical, and genetic investigations. The aim of this study was molecular characterization of the largest cohort of Iranian MPS patients (302 patients from 289 unrelated families), along with tracking their ethnicity and geographical origins. 185/289 patients were studied using an IEM-targeted NGS panel followed by complementary Sanger sequencing, which led to the diagnosis of 154 MPS patients and 5 non-MPS IEMs (diagnostic yield: 85.9%). Furthermore, 106/289 patients who were referred with positive findings went through re-analysis and confirmatory tests which confirmed MPS diagnosis in 104. Among the total of 258 MPS patients, 225 were homozygous, 90 harbored novel variants, and 9 had copy number variations. MPS IV was the most common type (34.8%) followed by MPS I (22.7%) and MPS VI (22.5%). Geographical origin analysis unveiled a pattern of distribution for frequent variants in ARSB (c.430G>A, c.962T>C [p.Leu321Pro], c.281C>A [p.Ser94*]), GALNS (c.319G>A [p.Ala107Thr], c.860C>T [p.Ser287Leu], c.1042A>G [p.Thr348Ala]), and IDUA (c.1A>C [p.Met1Leu], c.1598C>G [p.Pro533Arg], c.1562_1563insC [p.Gly522Argfs*50]). Our extensive patient cohort reveals the genetic and geographic landscape of MPS in Iran, which provides insight into genetic epidemiology of MPS and can facilitate a more cost-effective, time-efficient diagnostic approach based on the region-specific variants. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- Saeed Reza Ghaffari
- Fetal Health Research Center, Hope Generation Foundation, Tehran, Iran.,Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran.,Gene Clinic, Tehran, Iran
| | - Maryam Rafati
- Fetal Health Research Center, Hope Generation Foundation, Tehran, Iran.,Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | - Mahdi Shadnoush
- Department of Clinical Nutrition, Faculty of Nutrition & Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Shokooh Pourbabaee
- Deputy of Curative Affairs, Ministry of Health and Medical Education, Tehran, Iran
| | - Mohammad Aghighi
- Transplantation and Diseases Administrationو Deputy of Curative Affairs, Ministry of Health and Medical Education, Tehran, Iran
| | - Siamak Mirab Samiee
- Food and Drug Laboratory Research Center, Tehran, Iran.,General Reference Health Laboratory, Ministry of Health and Medical Education, Tehran, IR
| | - Jamshid Kermanchi
- Transplantation and Diseases Administrationو Deputy of Curative Affairs, Ministry of Health and Medical Education, Tehran, Iran
| | | | | | - Davoud Amirkashani
- Division of Endocrinology and Metabolism, Ali-Asghar Children's Hospital, Iran University of Medical Sciences, Tehran, IR
| | - Aria Setoodeh
- Children's Medical Center, Growth and Development Research Center, Tehran University of Medical Sciences, Tehran, Tehran, IR
| | - Peymaneh Sarkhail
- Personalized Medicine and Genometabolomics Research Center, Hope Generation Foundation, Tehran, Iran
| | - Reza Shervin Badv
- Department of Pediatrics, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Tehran, IR
| | - Majid Aminzadeh
- Diabetes Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Khuzestan, IR
| | - Siamak Shiva
- Pediatric Health Research Center, Tabriz University of Medical Sciences, Tabriz, East Azerbaijan, IR
| | - Peyman Eshraghi
- Mashhad University of Medical Sciences, Mashhad, Khorasan Razavi, IR
| | - Hossein Moravej
- Neonatal Research Center, Shiraz University of Medical Sciences, Shiraz, Fars, IR
| | - Mahin Hashemipour
- Metabolic Liver Disease Research Center, Isfahan University of Medical Sciences, Isfahan, Isfahan, IR
| | - Noushin Rostampour
- Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences Isfahan, Isfahan, Isfahan, IR
| | - Amir Ali Hamidieh
- Pediatric Cell and Gene Therapy Research Center, Tehran University of Medical Sciences, Tehran, Tehran, IR
| | - Bibi Shahin Shamsian
- Pediatric Congenital Hematologic Disorders Research Center, Research, Institute for Children's Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Sedigheh Shams
- Department of Pathology, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Tehran, IR
| | - Daniel Zamanfar
- Diabetes Research Center, Mazandaran University of Medical Sciences, Sari, IR
| | - Ayoub Ebrahimi
- Pediatric Health Research Center, Tabriz University of Medical Sciences, Tabriz, East Azerbaijan, IR
| | - Ali Otadi
- The University of British Columbia, Faculty of Science, Vancouver, BC, Canada
| | - Seyedeh Zahra Tara
- Pediatric Endocrinology Department, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Zeinab Barati
- Fetal Health Research Center, Hope Generation Foundation, Tehran, Iran.,Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | - Laya Fakhri
- Fetal Health Research Center, Hope Generation Foundation, Tehran, Iran.,Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | - Azadeh Hoseini
- Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | - Hosna Amiri
- Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | - Somayeh Ramandi
- Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | - Niusha Mostofinezhad
- Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | | | | | - Mahsa Khosravi
- Islamic Azad University Tehran Medical Sciences, Tehran, Tehran, IR
| | - Masoome Saadati
- Islamic Azad University Tehran North Branch, Tehran, Tehran, IR
| | - Fatemeh Hoseininasab
- Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | | | | |
Collapse
|
28
|
Corsini S, Pedrini E, Patavino C, Gnoli M, Lanza M, Sangiorgi L. An Easy-to-Use Approach to Detect CNV From Targeted NGS Data: Identification of a Novel Pathogenic Variant in MO Disease. Front Endocrinol (Lausanne) 2022; 13:874126. [PMID: 35837302 PMCID: PMC9273874 DOI: 10.3389/fendo.2022.874126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 05/25/2022] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Despite the new next-generation sequencing (NGS) molecular approaches implemented the genetic testing in clinical diagnosis, copy number variation (CNV) detection from NGS data remains difficult mainly in the absence of bioinformatics personnel (not always available among laboratory resources) and when using very small gene panels that do not meet commercial software criteria. Furthermore, not all large deletions/duplications can be detected with the Multiplex Ligation-dependent Probe Amplification (MLPA) technique due to both the limitations of the methodology and no kits available for the most of genes. AIM We propose our experience regarding the identification of a novel large deletion in the context of a rare skeletal disease, multiple osteochondromas (MO), using and validating a user-friendly approach based on NGS coverage data, which does not require any dedicated software or specialized personnel. METHODS The pipeline uses a simple algorithm comparing the normalized coverage of each amplicon with the mean normalized coverage of the same amplicon in a group of "wild-type" samples representing the baseline. It has been validated on 11 samples, previously analyzed by MLPA, and then applied on 20 patients with MO but negative for the presence of pathogenic variants in EXT1 or EXT2 genes. Sensitivity, specificity, and accuracy were evaluated. RESULTS All the 11 known CNVs (exon and multi-exon deletions) have been detected with a sensitivity of 97.5%. A novel EXT2 partial exonic deletion c. (744-122)-?_804+?del -out of the MLPA target regions- has been identified. The variant was confirmed by real-time quantitative Polymerase Chain Reaction (qPCR). CONCLUSION In addition to enhancing the variant detection rate in MO molecular diagnosis, this easy-to-use approach for CNV detection can be easily extended to many other diagnostic fields-especially in resource-limited settings or very small gene panels. Notably, it also allows partial-exon deletion detection.
Collapse
|
29
|
Lam BL, Leroy BP, Black G, Ong T, Yoon D, Trzupek K. Genetic testing and diagnosis of inherited retinal diseases. Orphanet J Rare Dis 2021; 16:514. [PMID: 34906171 PMCID: PMC8670140 DOI: 10.1186/s13023-021-02145-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 11/28/2021] [Indexed: 12/12/2022] Open
Abstract
Inherited retinal diseases (IRDs) are a diverse group of degenerative diseases of the retina that can lead to significant reduction in vision and blindness. Because of the considerable phenotypic overlap among IRDs, genetic testing is a critical step in obtaining a definitive diagnosis for affected individuals and enabling access to emerging gene therapy–based treatments and ongoing clinical studies. While advances in molecular diagnostic technologies have significantly improved the understanding of IRDs and identification of disease-causing variants, training in genetic diagnostics among ophthalmologists is limited. In this review, we will provide ophthalmologists with an overview of genetic testing for IRDs, including the types of available testing, variant interpretation, and genetic counseling. Additionally, we will discuss the clinical applications of genetic testing in the molecular diagnosis of IRDs through case studies.
Collapse
Affiliation(s)
- Byron L Lam
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, 900 NW 17th Street, Miami, FL, 33156, USA.
| | - Bart P Leroy
- Department of Ophthalmology, Ghent University and Ghent University Hospital, Ghent, Belgium.,Ophthalmic Genetics and Visual Electrophysiology, Division of Ophthalmology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Graeme Black
- UK Inherited Retinal Disease Consortium, Manchester, UK.,Genomics England Clinical Interpretation Partnership, Manchester, UK.,Manchester Centre for Genomic Medicine, St. Mary's Hospital, Manchester, UK
| | - Tuyen Ong
- Ring Therapeutics, Cambridge, MA, USA
| | | | - Karmen Trzupek
- Ocular and Rare Disease Genetics Services, InformedDNA, St Petersburg, FL, USA
| |
Collapse
|
30
|
Yang J, Zhou L, Ouyang J, Xiao X, Sun W, Li S, Zhang Q. Genotype-Phenotype Analysis of RPGR Variations: Reporting of 62 Chinese Families and a Literature Review. Front Genet 2021; 12:600210. [PMID: 34745198 PMCID: PMC8565807 DOI: 10.3389/fgene.2021.600210] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 04/27/2021] [Indexed: 02/05/2023] Open
Abstract
Purpose RPGR is the most common cause of X-linked retinitis pigmentosa (RP), of which female carriers are also frequently affected. The aim of the current study was to explore the RPGR variation spectrum and associated phenotype based on the data from our lab and previous studies. Methods Variants in RPGR were selected from exome sequencing data of 7,092 probands with different eye conditions. The probands and their available family members underwent comprehensive ocular examinations. Similar data were collected from previous reports through searches in PubMed, Web of Science, and Google Scholar. Systematic analyses of genotypes, phenotypes and their correlations were performed. Results A total of 46 likely pathogenic variants, including nine missense and one in-frame variants in RCC1-like domain and 36 truncation variants, in RPGR were detected in 62 unrelated families in our in-house cohort. In addition, a total of 585 variants, including 491 (83.9%) truncation variants, were identified from the literature. Systematic analysis of variants from our in-house dataset, literature, and gnomAD suggested that most of the pathogenic variants of RPGR were truncation variants while pathogenic missense and in-frame variants were enriched in the RCC1-like domain. Phenotypic variations were present between males and female carriers, including more severe refractive error but better best corrected visual acuity (BCVA) in female carriers than those in males. The male patients showed a significant reduction of BCVA with increase of age and males with exon1-14 variants presented a better BCVA than those with ORF15 variants. For female carriers, the BCVA also showed significant reduction with increase of age, but BCVA in females with exon1-14 variants was not significant difference compared with those with ORF15 variants. Conclusion Most pathogenic variants of RPGR are truncations. Missense and in-frame variants located outside of the RCC1-like domain might be benign and the pathogenicity criteria for these variants should be considered with greater caution. The BCVA and refractive error are different between males and female carriers. Increase of age and location of variants in ORF15 contribute to the reduction of BCVA in males. These results are valuable for understanding genotypes and phenotypes of RPGR.
Collapse
Affiliation(s)
- Junxing Yang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Lin Zhou
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Jiamin Ouyang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Xueshan Xiao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Wenmin Sun
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Shiqiang Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Qingjiong Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| |
Collapse
|
31
|
Marques JP, Marta A, Geada S, Carvalho AL, Menéres P, Murta J, Saraiva J, Silva R. Clinical/Demographic Functional Testing and Multimodal Imaging Differences between Genetically Solved and Unsolved Retinitis Pigmentosa. Ophthalmologica 2021; 245:134-143. [PMID: 34695833 DOI: 10.1159/000520305] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Accepted: 10/19/2021] [Indexed: 11/19/2022]
Abstract
INTRODUCTION The purpose of this study was to compare clinical/demographic functional testing and multimodal imaging features between genetically solved and genetically unsolved nonsyndromic retinitis pigmentosa (nsRP) patients. METHODS A cross-sectional study was conducted at an inherited retinal dystrophies reference center. Consecutive patients with nsRP and available genetic testing results performed between 2018 and 2020 were included. Genetic testing was clinically oriented, and variants were classified according to the American College of Medical Genetics and Genomics. Only class IV or V variants were considered disease-causing. Clinical/demographic, functional, and imaging features were compared between genetically unsolved (G1) and genetically solved (G2) patients. RESULTS A total of 175 patients (146 families) were included: 68 patients (59 families) in G1 and 107 patients (87 families) in G2. First symptoms <25 years, consanguinity, evidence for a particular inheritance pattern, and the absence of indicators for phenocopies were significantly more prevalent in G2. No significant differences were observed on best-corrected visual acuity. The visual field index and mean central retinal layer thickness were significantly higher in G1. The frequency of atypical features on multimodal imaging did not differ between groups. CONCLUSION Individual clinical/demographic functional testing and multimodal imaging features should be considered when counseling patients about the probability of identifying disease-causing variants.
Collapse
Affiliation(s)
- João Pedro Marques
- Department of Ophthalmology, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal.,Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal.,University Clinic of Ophthalmology, Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal
| | - Ana Marta
- Department of Ophthalmology, Centro Hospitalar e Universitário do Porto (CHUP), Porto, Portugal.,Instituto Ciências Biomédicas Abel Salazar (ICBAS), Porto, Portugal
| | - Sara Geada
- Department of Ophthalmology, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal
| | - Ana Luísa Carvalho
- Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal.,Department of Medical Genetics, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal.,University Clinic of Medical Genetics, Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal
| | - Pedro Menéres
- Department of Ophthalmology, Centro Hospitalar e Universitário do Porto (CHUP), Porto, Portugal.,Instituto Ciências Biomédicas Abel Salazar (ICBAS), Porto, Portugal
| | - Joaquim Murta
- Department of Ophthalmology, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal.,Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal.,University Clinic of Ophthalmology, Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal
| | - Jorge Saraiva
- Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal.,Department of Medical Genetics, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal.,University Clinic of Pediatrics, Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal
| | - Rufino Silva
- Department of Ophthalmology, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal.,Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal.,University Clinic of Ophthalmology, Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal
| |
Collapse
|
32
|
Lofaro FD, Mucciolo DP, Murro V, Pavese L, Quaglino D, Boraldi F. From Clinical Diagnosis to the Discovery of Multigene Rare Sequence Variants in Pseudoxanthoma elasticum: A Case Report. Front Med (Lausanne) 2021; 8:726856. [PMID: 34513887 PMCID: PMC8427021 DOI: 10.3389/fmed.2021.726856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 07/30/2021] [Indexed: 12/03/2022] Open
Abstract
Pseudoxanthoma elasticum (PXE) is a rare autosomal recessive disease clinically characterised by early cutaneous alterations, and by late clinically relevant ocular, and cardiovascular manifestations. ABCC6 genetic tests are used to confirm clinical PXE diagnosis, but this strategy may be rather challenging when only one ABCC6 pathogenic variant is found. A next-generation sequencing approach focusing on 362 genes related to the calcification process and/or to inherited retinal diseases was performed on a patient with clinical PXE diagnosis (skin papules and laxity, angioid streaks, and atrophy) who was carrier of only one ABCC6 rare sequence variant. Beside ABCC6, several rare sequence variants were detected which can contribute either to the occurrence of calcification (GGCX and SERPINF1 genes) and/or to ophthalmological manifestations (ABCA4, AGBL5, CLUAP1, and KCNV2 genes). This wide-spectrum analysis approach facilitates the identification of rare variants possibly involved in PXE, thus avoiding invasive skin biopsy as well as expensive and time-consuming diagnostic odyssey and allows to broaden and to deepen the knowledge on this complex rare disease and to improve patients' counselling, also with a future perspective of personalised medicine.
Collapse
Affiliation(s)
| | - Dario Pasquale Mucciolo
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Eye Clinic, Florence, Italy
| | - Vittoria Murro
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Eye Clinic, Florence, Italy
| | - Laura Pavese
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Eye Clinic, Florence, Italy
| | - Daniela Quaglino
- Department of Life Science, University of Modena and Reggio Emilia, Modena, Italy
| | - Federica Boraldi
- Department of Life Science, University of Modena and Reggio Emilia, Modena, Italy
| |
Collapse
|
33
|
Retinitis Punctata Albescens and RLBP1-Allied Phenotypes. OPHTHALMOLOGY SCIENCE 2021; 1:100052. [PMID: 36247817 PMCID: PMC9559097 DOI: 10.1016/j.xops.2021.100052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 08/04/2021] [Accepted: 08/06/2021] [Indexed: 11/21/2022]
Abstract
Purpose To identify relevant criteria for gene therapy based on clinical and genetic characteristics of rod–cone dystrophy associated with RLBP1 pathogenic variants in a large cohort comprising children and adults. Design Retrospective cohort study. Participants Patients with pathogenic variants in RLBP1 registered in a single French reference center specialized in inherited retinal dystrophies. Methods Clinical, multimodal imaging, and genetic findings were reviewed. Main Outcome Measures Age of onset; visual acuity; ellipsoid line length; nasal, temporal, and foveal retinal thickness; and pathogenic variants and related phenotypes, including Newfoundland rod–cone and Bothnia dystrophies (NFRCDs), were reappraised. Results Twenty-one patients (15 families) were included. The most frequent form was NFRCD with 12 patients (8 families) homozygous for the recurrent deletion of exons 7 through 9 in RLBP1 and 5 patients (4 families) with biallelic protein-truncating variants (2 novel: p.Gln16∗ and p.Tyr251∗). A novel combination of the p.Arg234Trp Bothnia variant with a nonsense variant in trans led to Bothnia dystrophy in 2 sisters. One proband carrying the p.Met266Lys Bothnia variant and in trans p.Arg121Trp and a second, with the p.Arg9Cys and p.Tyr111∗ combination, both demonstrated mild retinitis punctata albescens. Independently of genotype, all patients showed a visual acuity of worse than 20/200, an ellipsoid line width of less than 1000 μm, and a mean foveal thickness of less than 130 to 150 μm, with loss of both the interdigitation and ellipsoid lines. Conclusions The eligibility for RLBP1 gene therapy first should be determined according to the biallelic variant combination using a robust classification as proposed herein. An ellipsoid line width of more than 1200 μm and a central thickness of more than 130 to 150 μm with detectable ellipsoid and interdigitation lines should be 2 prerequisite imaging indicators for gene therapy.
Collapse
|
34
|
Duzkale N, Arslan U. Investigation of genotype-phenotype relationship in Turkish patients with inherited retinal disease by next generation sequencing. Ophthalmic Genet 2021; 42:674-684. [PMID: 34315337 DOI: 10.1080/13816810.2021.1952616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND Inherited retinal dystrophies (IRDs) are a group of retinal diseases genetically and clinically highly heterogeneous and associated with more than 300 genes. This study aims to investigate the genetic basis of Turkish patients with IRDs. MATERIALS AND METHODS In the study, genes related to retinal diseases in 86 IRDs patients were analyzed using the Next Generations Sequencing method (NGS). RESULTS The mean age of 86 patients was 35 and the mean age at diagnosis was 18. There was consanguinity between the parents of 62% of these patients. Fifty-six retinal disease-associated genes of 46 patients and 230 retinal disease-associated genes of 40 patients were examined. Genetic analysis provides a molecular diagnosis in a total of 53 (61.6%) patients. The genes responsible for the IRDs phenotype were frequently identified as ABCA4 (25%), EYS (11%), and RDH12 (9%). There was no significant difference between those with and without a molecular diagnosis in terms of demographic characteristics and family history. CONCLUSIONS Determination of genetic cause by NGS method in IRDs subgroups that are difficult to define by ophthalmic examination ensures that patients receive accurate diagnosis, treatment and counseling. This study contributed to the understanding of the genotype-phenotype relationship of Turkish patients with IRDs.
Collapse
Affiliation(s)
- Neslihan Duzkale
- Department of Medical Genetic, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Umut Arslan
- Department of Bioretina, Ankara University Technopolis, Ankara, Turkey
| |
Collapse
|
35
|
Sakti DH, Cornish EE, Mustafic N, Zaheer A, Retsas S, Rajagopalan S, Chung CW, Ewans L, McCluskey P, Nash BM, Jamieson RV, Grigg JR. MERTK retinopathy: biomarkers assessing vision loss. Ophthalmic Genet 2021; 42:706-716. [PMID: 34289798 DOI: 10.1080/13816810.2021.1955278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
PURPOSE Mer tyrosine kinase-retinitis pigmentosa (MERTK-RP) causes a primary defect in the retinal pigment epithelium, which subsequently affects rod and cone photoreceptors. The study aims to identify the most appropriate MERTK-RP biomarkers to measure disease progression for deciding the optimum therapeutic trial intervention time. MATERIALS AND METHODS Patients' data from baseline (BL) and last follow-up (LFU) were reviewed. Best corrected visual acuity (BCVA), spectral domain-optical coherence tomography (SD-OCT), ultra-widefield fundus autofluorescence (UWF-FAF) patterns, kinetic perimetry (KP), and electroretinography (ERG) parameters were analyzed. RESULTS Five patients were included with the mean age of 17.7 ± 14.4 years old (6.7-42.3) at BL and mean BCVA follow-up of 8.4 ± 5.1 years. Mean BCVA at BL and LFU were 0.84 ± 0.86 LogMAR and 1.14 ± 0.86 LogMAR, respectively. The BCVA decline rate was 0.05 ± 0.03 LogMAR units/year. Ellipzoid zones (EZ) were measurable in eight eyes with mean BL length of 1293.75 ± 421.07 µm and reduction of 140.95 ± 69.28 µm/year and mean BL CMT of 174.2 ± 37.52 µm with the rate of 11.2 ± 12.77 µm declining/year. Full-field ERG (ffERG) and pattern ERG (pERG) were barely recordable. UWF-FAF showed central macular hyper-autofluorescence (hyperAF). KP (III4e and V4e) was normal in two eyes, restricted nasally in four eyes, superior wedge defect in two eyes and undetectable in two eyes. The four restricted nasally KPs became worse, while the others stayed almost unchanged. CONCLUSIONS This cohort showed early visual loss, moderately rapid EZ reduction and macular hyperAF. EZ, CMT, and BCVA were consistently reduced. Relative rapid decline in these biomarkers reflecting visual function suggests an early and narrow timespan for intervention.
Collapse
Affiliation(s)
- Dhimas H Sakti
- Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Department of Ophthalmology, Faculty of Medicine, Public Health and Nursing; Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Elisa E Cornish
- Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Eye Genetics Research Unit, Children's Medical Research Institute, the Children's Hospital at Westmead, Save Sight Institute, University of Sydney, Sydney, NSW, Australia
| | - Nina Mustafic
- Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Afsah Zaheer
- Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Stephanie Retsas
- Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Sulekha Rajagopalan
- Department of Clinical Genetics, Liverpool Hospital, Liverpool BC, NSW, Australia
| | - Clara Wt Chung
- Department of Clinical Genetics, Liverpool Hospital, Liverpool BC, NSW, Australia.,School of Women's & Children's Health, University of NSW, Sydney, NSW, Australia
| | - Lisa Ewans
- Department of Clinical Genetics, Royal Prince Alfred Hospital, Camperdown, NSW, Australia.,Faculty of Medicine and Health Central Clinical School, Sydney Medical School, University of Sydney, Sydney, NSW, Australia
| | - Peter McCluskey
- Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Benjamin M Nash
- Eye Genetics Research Unit, Children's Medical Research Institute, the Children's Hospital at Westmead, Save Sight Institute, University of Sydney, Sydney, NSW, Australia.,Disciplines of Genomic Medicine & Child and Adolescent Health, Sydney Medical School, University of Sydney, Sydney, NSW, Australia.,Sydney Genome Diagnostics, Western Sydney Genetics Program, the Children's Hospital at Westmead, Sydney, NSW, Australia
| | - Robyn V Jamieson
- Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Eye Genetics Research Unit, Children's Medical Research Institute, the Children's Hospital at Westmead, Save Sight Institute, University of Sydney, Sydney, NSW, Australia.,Disciplines of Genomic Medicine & Child and Adolescent Health, Sydney Medical School, University of Sydney, Sydney, NSW, Australia.,Department of Clinical Genetics, Western Sydney Genetics Program, the Children's Hospital at Westmead, Sydney, NSW, Australia
| | - John R Grigg
- Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Eye Genetics Research Unit, Children's Medical Research Institute, the Children's Hospital at Westmead, Save Sight Institute, University of Sydney, Sydney, NSW, Australia
| |
Collapse
|
36
|
Testa F, Sodi A, Signorini S, Di Iorio V, Murro V, Brunetti-Pierri R, Valente EM, Karali M, Melillo P, Banfi S, Simonelli F. Spectrum of Disease Severity in Nonsyndromic Patients With Mutations in the CEP290 Gene: A Multicentric Longitudinal Study. Invest Ophthalmol Vis Sci 2021; 62:1. [PMID: 34196655 PMCID: PMC8267213 DOI: 10.1167/iovs.62.9.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Purpose The purpose of this study was to perform a detailed longitudinal phenotyping and genetic characterization of 32 Italian patients with a nonsyndromic retinal dystrophy and mutations in the CEP290 gene. Methods We reviewed the clinical history and examinations of 32 patients with a nonsyndromic retinal dystrophy due to mutations in the CEP290 gene, followed up (mean follow-up: 5.9 years) at 3 Italian centers. The clinical examinations included: best corrected visual acuity (BCVA), optical coherence tomography (OCT), and full-field electroretinogram (ERG). Results Patients (mean age = 19.0 ± 3.4 years) had a mean BCVA of 1.73 ± 0.20 logMAR. Longitudinal analysis of BCVA showed a nonsignificant decline. Central retinal thickness (CRT) declined significantly with age at an exponential rate of 1.0%/year (P = 0.001). At disease onset, most patients (19/32; 49.4%) had nystagmus. The absence of nystagmus was significantly associated with better BCVA and more preserved CRT (P < 0.05). ERG showed undetectable responses in most patients (64.0%), whereas reduced scotopic and photopic responses were observed in four patients (16.0%) who had no nystagmus. We identified 35 different variants, among which 12 were novel. Our genotype-phenotype correlation analysis shows a significantly worse BCVA in patients harboring a loss-of-function mutation and the deep-intronic variant c.2991+1655A>G. Conclusions Our study highlights a mild phenotype of the disease, characterized by absence of nystagmus, good visual acuity, considerably preserved retinal morphology, and recordable ERG, confirming the wide spectrum of CEP290-related retinal dystrophies. Finally, in our cohort, the deep intronic variant c.2991+1655A>G was associated with a more severe phenotype.
Collapse
Affiliation(s)
- Francesco Testa
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli", Naples, Italy
| | - Andrea Sodi
- Eye Clinic, Neuromuscolar and Sense Organs Department, Careggi University Hospital, Florence, Italy
| | - Sabrina Signorini
- Unit of Child Neurology and Psychiatry, IRCCS C. Mondino Foundation, Pavia, Italy
| | - Valentina Di Iorio
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli", Naples, Italy
| | - Vittoria Murro
- Eye Clinic, Neuromuscolar and Sense Organs Department, Careggi University Hospital, Florence, Italy
| | - Raffaella Brunetti-Pierri
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli", Naples, Italy
| | - Enza Maria Valente
- Department of Molecular Medicine, University of Pavia, Pavia, Italy.,Neurogenetics Unit, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Marianthi Karali
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli", Naples, Italy.,Telethon Institute of Genetics and Medicine, Pozzuoli, Italy
| | - Paolo Melillo
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli", Naples, Italy
| | - Sandro Banfi
- Telethon Institute of Genetics and Medicine, Pozzuoli, Italy.,Medical Genetics, Department of Precision Medicine, Università degli Studi della Campania "Luigi Vanvitelli", Naples, Italy
| | - Francesca Simonelli
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli", Naples, Italy
| |
Collapse
|
37
|
Babić Božović I, Maver A, Leonardis L, Meznaric M, Osredkar D, Peterlin B. Diagnostic yield of exome sequencing in myopathies: Experience of a Slovenian tertiary centre. PLoS One 2021; 16:e0252953. [PMID: 34106991 PMCID: PMC8189452 DOI: 10.1371/journal.pone.0252953] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 05/25/2021] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Our aim was to present the experience of systematic, routine use of next generation sequencing (NGS) in clinical diagnostics of myopathies. METHODS Exome sequencing was performed on patients with high risk for inherited myopathy, which were selected based on the history of the disease, family history, clinical presentation, and diagnostic workup. Exome target capture was performed, followed by sequencing on HiSeq 2500 or MiSeq platforms. Data analysis was performed using internally developed bioinformatic pipeline. RESULTS The study comprised 86 patients, including 22 paediatric cases (26%). The largest group were patients referred with an unspecified myopathy (47%), due to non-specific or incomplete clinical and laboratory findings, followed by congenital myopathies (22%) and muscular dystrophies (22%), congenital myotonias (6%), and mitochondrial myopathies (3%). Altogether, a diagnostic yield was 52%; a high diagnostic rate was present in paediatric patients (64%), while in patients with unspecified myopathies the rate was 35%. We found 51 pathogenic/likely pathogenic variants in 23 genes and two pathogenic copy number variations. CONCLUSION Our results provide evidence that phenotype driven exome analysis diagnostic approach facilitates the diagnostic rate of complex, heterogeneous disorders, such as myopathies, particularly in paediatric patients and patients with unspecified myopathies.
Collapse
Affiliation(s)
- Ivana Babić Božović
- Clinical Institute of Genomic Medicine, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Aleš Maver
- Clinical Institute of Genomic Medicine, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Lea Leonardis
- Institute of Clinical Neurophysiology, University Medical Centre Ljubljana, Ljubljana, Slovenia
- Department of Neurology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Marija Meznaric
- Institute of Anatomy, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Damjan Osredkar
- Department of Paediatric Neurology, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Borut Peterlin
- Clinical Institute of Genomic Medicine, University Medical Centre Ljubljana, Ljubljana, Slovenia
| |
Collapse
|
38
|
Jaffal L, Joumaa H, Mrad Z, Zeitz C, Audo I, El Shamieh S. The genetics of rod-cone dystrophy in Arab countries: a systematic review. Eur J Hum Genet 2021; 29:897-910. [PMID: 33188265 PMCID: PMC8187393 DOI: 10.1038/s41431-020-00754-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 10/02/2020] [Accepted: 10/20/2020] [Indexed: 02/07/2023] Open
Abstract
Since a substantial difference in the prevalence of genetic causes of rod-cone dystrophy (RCD) was found among different populations, we conducted a systematic review of the genetic findings associated with RCD in Arab countries. Of the 816 articles retrieved from PubMed, 31 studies conducted on 407 participants from 11 countries were reviewed. Next-generation sequencing (NGS) was the most commonly used technique (68%). Autosomal recessive pattern was the most common pattern of inheritance (97%) and half of the known genes associated with RCD (32/63) were identified. In the Kingdom of Saudi Arabia, in addition to RP1 (20%) and TULP1 (20%), gene defects in EYS (8%) and CRB1 (7%) were also prevalently mutated. In North Africa, the main gene defects were in MERTK (18%) and RLBP1 (18%). Considering all countries, RP1 and TULP1 remained the most prevalently mutated. Variants in TULP1, RP1, EYS, MERTK, and RLBP1 were the most prevalent, possibly because of founder effects. On the other hand, only ten Individuals were found to have dominant or X-linked RCD. This is the first time a catalog of RCD genetic variations has been established in subjects from the Arabi countries. Although the last decade has seen significant interest, expertise, and an increase in RCD scientific publication, much work needs to be conducted.
Collapse
Affiliation(s)
- Lama Jaffal
- Department of Biological and Environmental Sciences, Faculty of Science, Beirut Arab University, Debbieh, 1107 2809, Lebanon
- Rammal Hassan Rammal Research Laboratory, Physiotoxicity (PhyTox), Faculty of Sciences, Lebanese University, Nabatieh, 1700, Lebanon
| | - Hawraa Joumaa
- Rammal Hassan Rammal Research Laboratory, Physiotoxicity (PhyTox), Faculty of Sciences, Lebanese University, Nabatieh, 1700, Lebanon
| | - Zamzam Mrad
- Rammal Hassan Rammal Research Laboratory, Physiotoxicity (PhyTox), Faculty of Sciences, Lebanese University, Nabatieh, 1700, Lebanon
| | - Christina Zeitz
- Sorbonne Universités, INSERM, CNRS, Institut de la Vision, Paris, 75012, France
| | - Isabelle Audo
- Sorbonne Universités, INSERM, CNRS, Institut de la Vision, Paris, 75012, France
- CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC1423, 28 rue de Charenton, F-75012, Paris, France
- University College London Institute of Ophthalmology, London, EC1V 9EL, UK
| | - Said El Shamieh
- Department of Medical Laboratory Technology, Faculty of Health Sciences, Beirut Arab University, Beirut, 1107 2809, Lebanon.
| |
Collapse
|
39
|
Mizobuchi K, Hayashi T, Oishi N, Kubota D, Kameya S, Higasa K, Futami T, Kondo H, Hosono K, Kurata K, Hotta Y, Yoshitake K, Iwata T, Matsuura T, Nakano T. Genotype-Phenotype Correlations in RP1-Associated Retinal Dystrophies: A Multi-Center Cohort Study in JAPAN. J Clin Med 2021; 10:jcm10112265. [PMID: 34073704 PMCID: PMC8197273 DOI: 10.3390/jcm10112265] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 05/14/2021] [Accepted: 05/21/2021] [Indexed: 12/13/2022] Open
Abstract
Background: Little is known about genotype–phenotype correlations of RP1-associated retinal dystrophies in the Japanese population. We aimed to investigate the genetic spectrum of RP1 variants and provide a detailed description of the clinical findings in Japanese patients. Methods: In total, 607 patients with inherited retinal diseases were examined using whole-exome/whole-genome sequencing (WES/WGS). PCR-based screening for an Alu element insertion (c.4052_4053ins328/p.Tyr1352AlafsTer9) was performed in 18 patients with autosomal-recessive (AR)-retinitis pigmentosa (RP) or AR-cone dystrophy (COD)/cone-rod dystrophy (CORD), including seven patients with heterozygous RP1 variants identified by WES/WGS analysis, and 11 early onset AR-RP patients, in whom no pathogenic variant was identified. We clinically examined 25 patients (23 families) with pathogenic RP1 variants, including five patients (five families) with autosomal-dominant (AD)-RP, 13 patients (11 families) with AR-RP, and seven patients (seven families) with AR-COD/CORD. Results: We identified 18 pathogenic RP1 variants, including seven novel variants. Interestingly, the Alu element insertion was the most frequent variant (32.0%, 16/50 alleles). The clinical findings revealed that the age at onset and disease progression occurred significantly earlier and faster in AR-RP patients compared to AD-RP or AR-COD/CORD patients. Conclusions: Our results suggest a genotype–phenotype correlation between variant types/locations and phenotypes (AD-RP, AR-RP, and AR-COD/CORD), and the Alu element insertion was the most major variant in Japanese patients with RP1-associated retinal dystrophies.
Collapse
Affiliation(s)
- Kei Mizobuchi
- Department of Ophthalmology, The Jikei University School of Medicine, 3-19-18, Nishi-shimbashi, Minato-ku, Tokyo 105-8471, Japan; (T.H.); (T.N.)
- Correspondence: ; Tel.: +81-3-3433-1111
| | - Takaaki Hayashi
- Department of Ophthalmology, The Jikei University School of Medicine, 3-19-18, Nishi-shimbashi, Minato-ku, Tokyo 105-8471, Japan; (T.H.); (T.N.)
- Department of Ophthalmology, Katsushika Medical Center, The Jikei University School of Medicine, 6-41-2 Aoto, Katsushika-ku, Tokyo 125-8506, Japan
| | - Noriko Oishi
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, 1715 Kamagari, Inzai, Chiba 270-1694, Japan; (N.O.); (D.K.); (S.K.)
| | - Daiki Kubota
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, 1715 Kamagari, Inzai, Chiba 270-1694, Japan; (N.O.); (D.K.); (S.K.)
| | - Shuhei Kameya
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, 1715 Kamagari, Inzai, Chiba 270-1694, Japan; (N.O.); (D.K.); (S.K.)
| | - Koichiro Higasa
- Department of Genome Analysis, Institute of Biomedical Science, Kansai Medical University, 2-5-1 Shinmachi, Hirakata, Osaka 573-1010, Japan;
| | - Takuma Futami
- Department of Ophthalmology, University of Occupational and Environmental Health, 1-1, Iseigaoka, Yahatanishi-ku Kitakyushu-shi, Fu-kuoka 807-8555, Japan; (T.F.); (H.K.)
| | - Hiroyuki Kondo
- Department of Ophthalmology, University of Occupational and Environmental Health, 1-1, Iseigaoka, Yahatanishi-ku Kitakyushu-shi, Fu-kuoka 807-8555, Japan; (T.F.); (H.K.)
| | - Katsuhiro Hosono
- Department of Ophthalmology, Hamamatsu University School of Medicine, 1-20-1, Handayama, Higashi-ku, Shizuoka, Hamamatsu 431-3192, Japan; (K.H.); (K.K.); (Y.H.)
| | - Kentaro Kurata
- Department of Ophthalmology, Hamamatsu University School of Medicine, 1-20-1, Handayama, Higashi-ku, Shizuoka, Hamamatsu 431-3192, Japan; (K.H.); (K.K.); (Y.H.)
| | - Yoshihiro Hotta
- Department of Ophthalmology, Hamamatsu University School of Medicine, 1-20-1, Handayama, Higashi-ku, Shizuoka, Hamamatsu 431-3192, Japan; (K.H.); (K.K.); (Y.H.)
| | - Kazutoshi Yoshitake
- National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo 152-8902, Japan; (K.Y.); (T.I.)
| | - Takeshi Iwata
- National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo 152-8902, Japan; (K.Y.); (T.I.)
| | - Tomokazu Matsuura
- Department of Laboratory Medicine, The Jikei University School of Medicine, 3-19-18, Nishi-shimbashi, Minato-ku, Tokyo 105-8471, Japan;
| | - Tadashi Nakano
- Department of Ophthalmology, The Jikei University School of Medicine, 3-19-18, Nishi-shimbashi, Minato-ku, Tokyo 105-8471, Japan; (T.H.); (T.N.)
| |
Collapse
|
40
|
Thorsteinsson DA, Stefansdottir V, Eysteinsson T, Thorisdottir S, Jonsson JJ. Molecular genetics of inherited retinal degenerations in Icelandic patients. Clin Genet 2021; 100:156-167. [PMID: 33851411 PMCID: PMC8360171 DOI: 10.1111/cge.13967] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 04/07/2021] [Accepted: 04/10/2021] [Indexed: 12/22/2022]
Abstract
The study objective was to delineate the genetics of inherited retinal degenerations (IRDs) in Iceland, a small nation of 364.000 and a genetic isolate. Benefits include delineating novel pathogenic genetic variants and defining genetically homogenous patients as potential investigative molecular therapy candidates. The study sample comprised patients with IRD in Iceland ascertained through national centralized genetic and ophthalmological services at Landspitali, a national social support institute, and the Icelandic patient association. Information on patients' disease, syndrome, and genetic testing was collected in a clinical registry. Variants were reevaluated according to ACMG/AMP guidelines. Overall, 140 IRD patients were identified (point prevalence of 1/2.600), of which 70 patients had a genetic evaluation where two-thirds had an identified genetic cause. Thirteen disease genes were found in patients with retinitis pigmentosa, with the RLBP1 gene most common (n = 4). The c.1073 + 5G > A variant in the PRPF31 gene was homozygous in two RP patients. All tested patients with X-linked retinoschisis (XLRS) had the same possibly unique RS1 pathogenic variant, c.441G > A (p.Trp147X). Pathologic variants and genes for IRDs in Iceland did not resemble those described in ancestral North-Western European nations. Four variants were reclassified as likely pathogenic. One novel pathogenic variant defined a genetically homogenous XLRS patient group.
Collapse
Affiliation(s)
| | - Vigdis Stefansdottir
- Department of Genetics and Molecular Medicine, Landspitali - National University Hospital of Iceland, Reykjavik, Iceland
| | - Thor Eysteinsson
- Department of Physiology, BioMedical Center, Faculty of Medicine, University of Iceland, Reykjavik, Iceland.,Department of Ophthalmology, Landspitali - National University Hospital of Iceland, Reykjavik, Iceland
| | - Sigridur Thorisdottir
- Department of Ophthalmology, Landspitali - National University Hospital of Iceland, Reykjavik, Iceland
| | - Jon J Jonsson
- Department of Genetics and Molecular Medicine, Landspitali - National University Hospital of Iceland, Reykjavik, Iceland.,Department of Biochemistry and Molecular Biology, BioMedical Center, Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| |
Collapse
|
41
|
Vilaplana F, Ros A, Garcia B, Blanco I, Castellanos E, Edwards NJ, Valldeperas X, Ruiz-Bilbao S, Sabala A. Clinical characteristics, imaging findings, and genetic results of a patient with CEP290-related cone-rod dystrophy. Ophthalmic Genet 2021; 42:474-479. [PMID: 33886416 DOI: 10.1080/13816810.2021.1916827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
PURPOSE To describe the clinical characteristics, the imaging findings, and the genetic results of a patient with cone-rod dystrophy (CORD) related to mutations in CEP290. METHODS A case report of atypical CEP290-related CORD. Ophthalmological examination was performed, including best-corrected visual acuity (BCVA), fundus photography, fundus autofluorescence (FAF) imaging, optical coherence tomography (OCT), a visual field test, and electroretinography testing. The genetic test was performed by next-generation sequencing (NGS)-based panel test containing 336 genes. RESULTS A 57-year-old female who had reported a visual loss for 5 years. BCVA was 20/100 in both eyes. The fundus examination revealed a hypopigmented halo around the fovea, showing a paracentral hyperautofluorescent ring on FAF. OCT demonstrated the presence of atrophy in the outer retinal layers. The genetic test identified the probably pathogenic variants c.4028delA and c.5254C>T in compound heterozygosis in CEP290. CONCLUSIONS This is the first report to present the clinical characteristics, imaging findings, and genetic test results of a patient with CEP290-related CORD. Our case contributes to expanding the clinical involvement of CEP290 pathogenic variants. This study indicates that CEP290-related CORD may have a mild phenotype with late-onset dystrophy, making these patients interesting candidates for innovative treatments such as genetic therapeutic approaches.
Collapse
Affiliation(s)
- Ferran Vilaplana
- Department of Ophthalmology, Hospital Universitari Germans Trias i Pujol, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Andrea Ros
- Genetic Counseling Unit, Genetics Service, Hospital Universitari Germans Trias i Pujol, Barcelona, Spain
| | - Belen Garcia
- Genetic Counseling Unit, Genetics Service, Hospital Universitari Germans Trias i Pujol, Barcelona, Spain
| | - Ignacio Blanco
- Genetic Counseling Unit, Genetics Service, Hospital Universitari Germans Trias i Pujol, Barcelona, Spain
| | - Elisabeth Castellanos
- Clinical Genomics Unit, Genetics Service, Hospital Universitari Germans Trias i Pujol, Barcelona, Spain.,Hereditary Cancer Group, Germans Trias Research Institute, IGTP, Barcelona, Spain
| | | | - Xavier Valldeperas
- Department of Ophthalmology, Hospital Universitari Germans Trias i Pujol, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Susana Ruiz-Bilbao
- Department of Ophthalmology, Hospital Universitari Germans Trias i Pujol, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Antonio Sabala
- Department of Ophthalmology, Hospital Universitari Germans Trias i Pujol, Universitat Autònoma de Barcelona, Barcelona, Spain
| |
Collapse
|
42
|
Bolz HJ. Diagnostic Analyses of Retinal Dystrophy Genes: Current Status and Perspective. Klin Monbl Augenheilkd 2021; 238:261-266. [PMID: 33784789 DOI: 10.1055/a-1386-5361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Over the past decade, novel high-throughput DNA sequencing technologies have revolutionised both research and diagnostic testing for monogenic disorders. This applies particularly to genetically very heterogeneous disorders like retinal dystrophies (RDs). Next-generation sequencing (NGS) today is considered as reliable as Sanger sequencing, which had been the gold standard for decades. Today, comprehensive NGS-based diagnostic testing reveals the causative mutations in the majority of RD patients, with important implications for genetic counselling for recurrence risks and personalised medical management (from interdisciplinary surveillance to prophylactic measures and, albeit yet rare, [gene] therapy). While DNA sequencing is - in most cases - no longer the diagnostic bottleneck, one needs to be aware of interpretation pitfalls and dead ends. The advent of new (NGS) technologies will solve some of these issues. However, specialised medical geneticists who are familiar with the peculiarities of certain RD genes and closely interact with ophthalmologists will remain key to successful RD research and diagnostic testing for the benefit of the patients. This review sheds light on the current state of the field, its challenges and potential solutions.
Collapse
Affiliation(s)
- Hanno Jörn Bolz
- Humangenetik, Senckenberg Zentrum für Humangenetik, Frankfurt, Germany.,Humangenetik, University Hospital of Cologne, Cologne, Germany
| |
Collapse
|
43
|
Clinical Phenotype of PDE6B-Associated Retinitis Pigmentosa. Int J Mol Sci 2021; 22:ijms22052374. [PMID: 33673512 PMCID: PMC7956818 DOI: 10.3390/ijms22052374] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 02/17/2021] [Accepted: 02/21/2021] [Indexed: 11/25/2022] Open
Abstract
In this retrospective, longitudinal, observational cohort study, we investigated the phenotypic and genotypic features of retinitis pigmentosa associated with variants in the PDE6B gene. Patients underwent clinical examination and genetic testing at a single tertiary referral center, including best-corrected visual acuity (BCVA), kinetic visual field (VF), full-field electroretinography, full-field stimulus threshold, spectral domain optical coherence tomography, and fundus autofluorescence imaging. The genetic testing comprised candidate gene sequencing, inherited retinal disease gene panel sequencing, whole-genome sequencing, and testing for familial variants by Sanger sequencing. Twenty-four patients with mutations in PDE6B from 21 families were included in the study (mean age at the first visit: 32.1 ± 13.5 years). The majority of variants were putative splicing defects (8/23) and missense (7/23) mutations. Seventy-nine percent (38/48) of eyes had no visual acuity impairment at the first visit. Visual acuity impairment was mild in 4% (2/48), moderate in 13% (6/48), and severe in 4% (2/48). BCVA was symmetrical in the right and left eyes. The kinetic VF measurements were highly symmetrical in the right and left eyes, as was the horizontal ellipsoid zone (EZ) width. Regarding the genetic findings, 43% of the PDE6B variants found in our patients were novel. Thus, this study contributed substantially to the PDE6B mutation spectrum. The visual acuity impairment was mild in 83% of eyes, providing a window of opportunity for investigational new drugs. The EZ width was reduced in all patients and was highly symmetric between the eyes, making it a promising outcome measure. We expect these findings to have implications on the design of future PDE6B-related retinitis pigmentosa (RP) clinical trials.
Collapse
|
44
|
Wang J, Xiao X, Li S, Wang P, Sun W, Zhang Q. Dominant RP in the Middle While Recessive in Both the N- and C-Terminals Due to RP1 Truncations: Confirmation, Refinement, and Questions. Front Cell Dev Biol 2021; 9:634478. [PMID: 33681214 PMCID: PMC7935555 DOI: 10.3389/fcell.2021.634478] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 01/19/2021] [Indexed: 11/13/2022] Open
Abstract
RP1 truncation variants, including frameshift, nonsense, and splicing, are a common cause of retinitis pigmentosa (RP). RP1 is a unique gene where truncations cause either autosomal dominant RP (adRP) or autosomal recessive RP (arRP) depending on the location of the variants. This study aims to clarify the boundaries between adRP and arRP caused by RP1 truncation variants based on a systemic analysis of 165 RP1 variants from our in-house exome-sequencing data of 7,092 individuals as well as a thorough review of 185 RP1 variants from published literature. In our cohort, potential pathogenic variants were detected in 16 families, including 11 new and five previously described families. Of the 16, seven families with adRP had heterozygous truncations in the middle portion, while nine families with either arRP (eight) or macular degeneration had biallelic variants in the N- and C-terminals, involving 10 known and seven novel variants. In the literature, 147 truncations in RP1 were reported to be responsible for either arRP (85) or adRP (58) or both (four). An overall evaluation of RP1 causative variants suggested three separate regions, i.e., the N-terminal from c.1 (p.1) to c.1837 (p.613), the middle portion from c.1981 (p.661) to c.2749 (p.917), and the C-terminal from c.2816 (p.939) to c.6471 (p.2157), where truncations in the middle portion were associated with adRP, while those in the N- and C-terminals were responsible for arRP. Heterozygous truncations alone in the N- and C- terminals were unlikely pathogenic. However, conflict reports with reverse situation were present for 13 variants, suggesting a complicated pathogenicity awaiting to be further elucidated. In addition, pathogenicity for homozygous truncations around c.5797 and thereafter might also need to be further clarified, so as for missense variants and for truncations located in the two gaps. Our data not only confirmed and refined the boundaries between dominant and recessive RP1 truncations but also revealed unsolved questions valuable for further investigation. These findings remind us that great care is needed in interpreting the results of RP1 variants in clinical gene testing as well as similar features may also be present in some other genes.
Collapse
Affiliation(s)
- Junwen Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Xueshan Xiao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Shiqiang Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Panfeng Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Wenmin Sun
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Qingjiong Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| |
Collapse
|
45
|
Perea-Romero I, Gordo G, Iancu IF, Del Pozo-Valero M, Almoguera B, Blanco-Kelly F, Carreño E, Jimenez-Rolando B, Lopez-Rodriguez R, Lorda-Sanchez I, Martin-Merida I, Pérez de Ayala L, Riveiro-Alvarez R, Rodriguez-Pinilla E, Tahsin-Swafiri S, Trujillo-Tiebas MJ, Garcia-Sandoval B, Minguez P, Avila-Fernandez A, Corton M, Ayuso C. Genetic landscape of 6089 inherited retinal dystrophies affected cases in Spain and their therapeutic and extended epidemiological implications. Sci Rep 2021; 11:1526. [PMID: 33452396 PMCID: PMC7810997 DOI: 10.1038/s41598-021-81093-y] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 12/31/2020] [Indexed: 02/08/2023] Open
Abstract
Inherited retinal diseases (IRDs), defined by dysfunction or progressive loss of photoreceptors, are disorders characterized by elevated heterogeneity, both at the clinical and genetic levels. Our main goal was to address the genetic landscape of IRD in the largest cohort of Spanish patients reported to date. A retrospective hospital-based cross-sectional study was carried out on 6089 IRD affected individuals (from 4403 unrelated families), referred for genetic testing from all the Spanish autonomous communities. Clinical, demographic and familiar data were collected from each patient, including family pedigree, age of appearance of visual symptoms, presence of any systemic findings and geographical origin. Genetic studies were performed to the 3951 families with available DNA using different molecular techniques. Overall, 53.2% (2100/3951) of the studied families were genetically characterized, and 1549 different likely causative variants in 142 genes were identified. The most common phenotype encountered is retinitis pigmentosa (RP) (55.6% of families, 2447/4403). The most recurrently mutated genes were PRPH2, ABCA4 and RS1 in autosomal dominant (AD), autosomal recessive (AR) and X-linked (XL) NON-RP cases, respectively; RHO, USH2A and RPGR in AD, AR and XL for non-syndromic RP; and USH2A and MYO7A in syndromic IRD. Pathogenic variants c.3386G > T (p.Arg1129Leu) in ABCA4 and c.2276G > T (p.Cys759Phe) in USH2A were the most frequent variants identified. Our study provides the general landscape for IRD in Spain, reporting the largest cohort ever presented. Our results have important implications for genetic diagnosis, counselling and new therapeutic strategies to both the Spanish population and other related populations.
Collapse
Affiliation(s)
- Irene Perea-Romero
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain.,Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Gema Gordo
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
| | - Ionut F Iancu
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain.,Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Marta Del Pozo-Valero
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain.,Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Berta Almoguera
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain.,Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Fiona Blanco-Kelly
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain.,Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Ester Carreño
- Department of Ophthalmology, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
| | - Belen Jimenez-Rolando
- Department of Ophthalmology, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
| | - Rosario Lopez-Rodriguez
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
| | - Isabel Lorda-Sanchez
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain.,Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Inmaculada Martin-Merida
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain.,Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Lucia Pérez de Ayala
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
| | - Rosa Riveiro-Alvarez
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain.,Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Elvira Rodriguez-Pinilla
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
| | - Saoud Tahsin-Swafiri
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain.,Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Maria J Trujillo-Tiebas
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain.,Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | | | | | | | - Blanca Garcia-Sandoval
- Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain.,Department of Ophthalmology, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
| | - Pablo Minguez
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain.,Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Almudena Avila-Fernandez
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain.,Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Marta Corton
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain. .,Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain.
| | - Carmen Ayuso
- Department of Genetics, Health Research Institute-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain. .,Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain.
| |
Collapse
|
46
|
Bi-Allelic Pathogenic Variations in MERTK Including Deletions Are Associated with an Early Onset Progressive Form of Retinitis Pigmentosa. Genes (Basel) 2020; 11:genes11121517. [PMID: 33353011 PMCID: PMC7766129 DOI: 10.3390/genes11121517] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 12/09/2020] [Accepted: 12/10/2020] [Indexed: 12/20/2022] Open
Abstract
Bi-allelic pathogenic variants in MERTK cause retinitis pigmentosa (RP). Since deletions of more than one exon have been reported repeatedly for MERTK, CNV (copy number variation) analysis of next-generation sequencing (NGS) data has proven important in molecular genetic diagnostics of MERTK. CNV analysis was performed on NGS data of 677 individuals with inherited retinal diseases (IRD) and confirmed by quantitative RT-PCR analysis. Clinical evaluation was based on retrospective records. Clinical re-examination included visual field examination, dark adaption, scotopic and photopic full-field electroretinograms (ffERG), multifocal ERG (mfERG) and optic coherence tomography (OCT). Fourteen variants were detected in MERTK in six individuals, three of which were deletions of more than one exon. Clinical examinations of five out of six individuals revealed a severe phenotype with early-onset generalized retinal dystrophy with night blindness and progressive visual field loss; however, one individual had a milder phenotype. Three individuals had hearing impairments. We show that deletions represent a substantial part of the causative variants in MERTK and emphasize that CNV analysis should be included in the molecular genetic diagnostics of IRDs.
Collapse
|
47
|
Whole exome sequencing and homozygosity mapping reveals genetic defects in consanguineous Iranian families with inherited retinal dystrophies. Sci Rep 2020; 10:19413. [PMID: 33173045 PMCID: PMC7655865 DOI: 10.1038/s41598-020-75841-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 09/08/2020] [Indexed: 12/17/2022] Open
Abstract
Inherited retinal dystrophies (IRDs), displaying pronounced genetic and clinical heterogeneity, comprise of a broad range of diseases characterized by progressive retinal cell death and gradual loss of vision. By the combined use of whole exome sequencing (WES), SNP-array and WES-based homozygosity mapping, as well as directed DNA sequencing (Sanger), we have identified nine pathogenic variants in six genes (ABCA4, RPE65, MERTK, USH2A, SPATA7, TULP1) in 10 consanguineous Iranian families. Six of the nine identified variants were novel, including a putative founder mutation in ABCA4 (c.3260A>G, p.Glu1087Gly), detected in two families from Northeastern Iran. Our findings provide additional information to the molecular pathology of IRDs in Iran, hopefully contributing to better genetic counselling and patient management in the respective families from this country.
Collapse
|
48
|
Al-khuzaei S, Broadgate S, Halford S, Jolly JK, Shanks M, Clouston P, Downes SM. Novel Pathogenic Sequence Variants in NR2E3 and Clinical Findings in Three Patients. Genes (Basel) 2020; 11:E1288. [PMID: 33138239 PMCID: PMC7716234 DOI: 10.3390/genes11111288] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 10/21/2020] [Accepted: 10/28/2020] [Indexed: 01/08/2023] Open
Abstract
A retrospective review of the clinical records of patients seen at the Oxford Eye Hospital identified as having NR2E3 mutations was performed. The data included symptoms, best-corrected visual acuity, multimodal retinal imaging, visual fields and electrophysiology testing. Three participants were identified with biallelic NR2E3 pathogenic sequence variants detected using a targeted NGS gene panel, two of which were novel. Participant I was a Nepalese male aged 68 years, and participants II and III were white Caucasian females aged 69 and 10 years old, respectively. All three had childhood onset nyctalopia, a progressive decrease in central vision, and visual field loss. Patients I and III had photopsia, patient II had photosensitivity and patient III also had photophobia. Visual acuities in patients I and II were preserved even into the seventh decade, with the worst visual acuity measured at 6/36. Visual field constriction was severe in participant I, less so in II, and fields were full to bright targets targets in participant III. Electrophysiology testing in all three demonstrated loss of rod function. The three patients share some of the typical distinctive features of NR2E3 retinopathies, as well as a novel clinical observation of foveal ellipsoid thickening.
Collapse
Affiliation(s)
- Saoud Al-khuzaei
- Oxford Eye Hospital, John Radcliffe Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford OX3 9DU, UK; (S.A.-k.); (J.K.J.)
| | - Suzanne Broadgate
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neuroscience, University of Oxford, Level 6 John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK; (S.B.); (S.H.)
| | - Stephanie Halford
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neuroscience, University of Oxford, Level 6 John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK; (S.B.); (S.H.)
| | - Jasleen K. Jolly
- Oxford Eye Hospital, John Radcliffe Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford OX3 9DU, UK; (S.A.-k.); (J.K.J.)
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neuroscience, University of Oxford, Level 6 John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK; (S.B.); (S.H.)
| | - Morag Shanks
- Oxford Medical Genetics Laboratory, Oxford University Hospitals NHS Foundation Trust, Oxford OX3 7LE, UK; (M.S.); (P.C.)
| | - Penny Clouston
- Oxford Medical Genetics Laboratory, Oxford University Hospitals NHS Foundation Trust, Oxford OX3 7LE, UK; (M.S.); (P.C.)
| | - Susan M. Downes
- Oxford Eye Hospital, John Radcliffe Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford OX3 9DU, UK; (S.A.-k.); (J.K.J.)
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neuroscience, University of Oxford, Level 6 John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK; (S.B.); (S.H.)
| |
Collapse
|
49
|
Bolz HJ. Usher syndrome: diagnostic approach, differential diagnoses and proposal of an updated function-based genetic classification. MED GENET-BERLIN 2020. [DOI: 10.1515/medgen-2020-2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Abstract
Usher syndrome (USH) manifests with congenital and apparently isolated hearing loss, followed by retinal degeneration in later life. Therefore, and because of its high prevalence in the congenitally hearing-impaired population, USH is one of the most relevant deafness syndromes. Next-generation sequencing (NGS)-based testing can now provide most analyzed USH patients with a molecular diagnosis, based on mutations in 11 genes. Given the availability of several excellent articles on the clinical and biochemical basis of USH, this short review focuses on critical assessment of new genes announced as USH genes, clinical and genetic differential diagnoses and therapeutic developments. Because obsolete loci, disproved USH genes and the inclusion of genes whose mutations cause similar phenotypes have increasingly blurred genetic classification, a revision based on phenotype restricted to genes related to the Usher protein complex is proposed.
Collapse
Affiliation(s)
- Hanno J. Bolz
- Senckenberg Centre for Human Genetics , Weismüllerstr. 50 , Frankfurt am Main , Germany
| |
Collapse
|
50
|
Wang J, Liu H, Bertrand RE, Sarrion-Perdigones A, Gonzalez Y, Venken KJT, Chen R. A novel statistical method for interpreting the pathogenicity of rare variants. Genet Med 2020; 23:59-68. [PMID: 32884132 PMCID: PMC7796914 DOI: 10.1038/s41436-020-00948-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 08/11/2020] [Accepted: 08/12/2020] [Indexed: 01/09/2023] Open
Abstract
Purpose: To achieve the ultimate goal of personalized treatment of patients, accurate molecular diagnosis and precise interpretation of the impact of genetic variants on gene function is essential. With the sequencing cost becoming increasingly affordable, accurate distinguishing benign from pathogenic variants upon sequencing becomes the major bottleneck. Although large normal population sequence databases have become a key resource in filtering benign variants, they are not effective at filtering extremely rare variants. Methods: To address this challenge, we developed a novel statistical test by combining sequencing data from a patient cohort with a normal control population database. By comparing the expected and observed allele frequency in the patient cohort, variants that are likely benign can be identified. Results: The performance of this new method is evaluated on both simulated and real datasets coupled with experimental validation. As a result, we demonstrate this new test is well-powered to identify benign variants, particularly effective for variants with low frequency in the normal population. Conclusion: Overall, as a general test that can be applied to any type of variants in the context of all Mendelian diseases, our work provides a general framework for filtering benign variants with very low population allele frequency.
Collapse
Affiliation(s)
- Jun Wang
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Hehe Liu
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Renae Elaine Bertrand
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA.,Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Alejandro Sarrion-Perdigones
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Yezabel Gonzalez
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Koen J T Venken
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA.,Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX, USA
| | - Rui Chen
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA. .,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.
| |
Collapse
|