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Zhang Y, Guo X, Hao L, Tian M, Ma Y, Tang Y. Identification of a novel compound heterozygous pathogenic variant in MYO7A causing Usher syndrome type IB in a Chinese patient: a case report. J Int Med Res 2023; 51:3000605231218924. [PMID: 38141656 DOI: 10.1177/03000605231218924] [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] [Indexed: 12/25/2023] Open
Abstract
Herein, we report the clinical and genetic features of a patient with Usher syndrome type IB to improve our collective understanding of the disorder. The patient was a teenaged boy with congenital profound hearing loss, progressive visual loss, and vestibular hypoplasia; his parents were phenotypically normal. His pure tone audiometry hearing thresholds were 100 dB at all frequencies, and distortion product otoacoustic emission was not elicited at any frequencies in either ear. Moreover, an auditory brainstem response test at 100 dB normal hearing level revealed no relevant response waves, and a caloric test showed vestibular hypoplasia. Fundus examination revealed retinitis pigmentosa and a reduced visual field. The use of high-throughput sequencing technology to screen the patient's family lineage for deafness-related genes revealed that the patient carried a compound heterozygous pathogenic variant of MYO7A: c.541C > T and c.6364delG. This pathogenic variant has not previously been reported. Our findings may provide a basis for genetic counseling, effective treatment, and/or gene therapy for Usher syndrome.
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Affiliation(s)
- Ya'nan Zhang
- College of Traditional Chinese Medicine, Changchun University of Traditional Chinese Medicine, Changchun, China
| | - Xinyi Guo
- College of Traditional Chinese Medicine, Changchun University of Traditional Chinese Medicine, Changchun, China
| | - Ling Hao
- Department of Otolaryngology, Head & Neck Surgery, The First Hospital of Changchun University of Traditional Chinese Medicine, Changchun, China
| | - Meihui Tian
- College of Traditional Chinese Medicine, Changchun University of Traditional Chinese Medicine, Changchun, China
| | - Yuan Ma
- College of Basic Medical Science, Changchun University of Traditional Chinese Medicine, Changchun, China
| | - Yong Tang
- College of Clinical Medicine, Changchun University of Traditional Chinese Medicine, Changchun, China
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Wonkam A, Adadey SM, Schrauwen I, Aboagye ET, Wonkam-Tingang E, Esoh K, Popel K, Manyisa N, Jonas M, deKock C, Nembaware V, Cornejo Sanchez DM, Bharadwaj T, Nasir A, Everard JL, Kadlubowska MK, Nouel-Saied LM, Acharya A, Quaye O, Amedofu GK, Awandare GA, Leal SM. Exome sequencing of families from Ghana reveals known and candidate hearing impairment genes. Commun Biol 2022; 5:369. [PMID: 35440622 PMCID: PMC9019055 DOI: 10.1038/s42003-022-03326-8] [Citation(s) in RCA: 1] [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: 01/04/2022] [Accepted: 03/25/2022] [Indexed: 12/15/2022] Open
Abstract
We investigated hearing impairment (HI) in 51 families from Ghana with at least two affected members that were negative for GJB2 pathogenic variants. DNA samples from 184 family members underwent whole-exome sequencing (WES). Variants were found in 14 known non-syndromic HI (NSHI) genes [26/51 (51.0%) families], five genes that can underlie either syndromic HI or NSHI [13/51 (25.5%)], and one syndromic HI gene [1/51 (2.0%)]. Variants in CDH23 and MYO15A contributed the most to HI [31.4% (16/51 families)]. For DSPP, an autosomal recessive mode of inheritance was detected. Post-lingual expression was observed for a family segregating a MARVELD2 variant. To our knowledge, seven novel candidate HI genes were identified (13.7%), with six associated with NSHI (INPP4B, CCDC141, MYO19, DNAH11, POTEI, and SOX9); and one (PAX8) with Waardenburg syndrome. MYO19 and DNAH11 were replicated in unrelated Ghanaian probands. Six of the novel genes were expressed in mouse inner ear. It is known that Pax8-/- mice do not respond to sound, and depletion of Sox9 resulted in defective vestibular structures and abnormal utricle development. Most variants (48/60; 80.0%) have not previously been associated with HI. Identifying seven candidate genes in this study emphasizes the potential of novel HI genes discovery in Africa.
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Affiliation(s)
- Ambroise Wonkam
- Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Cape Town, 7925, South Africa.
- McKusick-Nathans Institute and Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
| | - Samuel Mawuli Adadey
- Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Cape Town, 7925, South Africa
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, LG 54, Ghana
| | - Isabelle Schrauwen
- Center for Statistical Genetics, Gertrude H. Sergievsky Center, and the Department of Neurology, Columbia University Medical Centre, New York, NY, 10032, USA
| | - Elvis Twumasi Aboagye
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, LG 54, Ghana
| | - Edmond Wonkam-Tingang
- Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Cape Town, 7925, South Africa
| | - Kevin Esoh
- Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Cape Town, 7925, South Africa
| | - Kalinka Popel
- Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Cape Town, 7925, South Africa
| | - Noluthando Manyisa
- Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Cape Town, 7925, South Africa
| | - Mario Jonas
- Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Cape Town, 7925, South Africa
| | - Carmen deKock
- Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Cape Town, 7925, South Africa
| | - Victoria Nembaware
- Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Cape Town, 7925, South Africa
| | - Diana M Cornejo Sanchez
- Center for Statistical Genetics, Gertrude H. Sergievsky Center, and the Department of Neurology, Columbia University Medical Centre, New York, NY, 10032, USA
| | - Thashi Bharadwaj
- Center for Statistical Genetics, Gertrude H. Sergievsky Center, and the Department of Neurology, Columbia University Medical Centre, New York, NY, 10032, USA
| | - Abdul Nasir
- Department of Molecular Science and Technology, Ajou University, Suwon-si, Republic of Korea
| | - Jenna L Everard
- Center for Statistical Genetics, Gertrude H. Sergievsky Center, and the Department of Neurology, Columbia University Medical Centre, New York, NY, 10032, USA
| | - Magda K Kadlubowska
- Center for Statistical Genetics, Gertrude H. Sergievsky Center, and the Department of Neurology, Columbia University Medical Centre, New York, NY, 10032, USA
| | - Liz M Nouel-Saied
- Center for Statistical Genetics, Gertrude H. Sergievsky Center, and the Department of Neurology, Columbia University Medical Centre, New York, NY, 10032, USA
| | - Anushree Acharya
- Center for Statistical Genetics, Gertrude H. Sergievsky Center, and the Department of Neurology, Columbia University Medical Centre, New York, NY, 10032, USA
| | - Osbourne Quaye
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, LG 54, Ghana
| | - Geoffrey K Amedofu
- Department of Eye, Ear, Nose, and Throat, School of Medical Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Gordon A Awandare
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, LG 54, Ghana
| | - Suzanne M Leal
- Center for Statistical Genetics, Gertrude H. Sergievsky Center, and the Department of Neurology, Columbia University Medical Centre, New York, NY, 10032, USA.
- Taub Institute for Alzheimer's Disease and the Aging Brain, Columbia University Medical Centre, New York, NY, 10032, USA.
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Torkamandi S, Bayat S, Mirfakhraie R, Rezaei S, Askari M, Piltan S, Gholami M. Targeted sequencing of CDH23 and GJB2 genes in an Iranian pedigree with Usher syndrome and non-syndromic hearing loss. GENE REPORTS 2021. [DOI: 10.1016/j.genrep.2021.101149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Awan AI, Abdul Raffay E, Liaqat A, Hassan T, Khan M. Are Consanguineous Marriages to Blame for Usher Syndrome Type 1, a Rare Disease in Pakistan? Cureus 2020; 12:e11117. [PMID: 33240713 PMCID: PMC7682543 DOI: 10.7759/cureus.11117] [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] [Indexed: 11/10/2022] Open
Abstract
Usher syndrome type I is a rare genetic autosomal recessive disease caused by mutations in specific genes that provide instructions for making proteins involved in normal hearing, vision, and balance. It is characterized by hearing impairment due to the inability of auditory nerves to send sensory input to the brain leading to hearing loss along with retinitis pigmentosa (RP), which is a progressive, bilateral, symmetrical retinal degeneration involving photoreceptor cells. We report a 32-year-old male patient who presented to us with complaints of night blindness and progressive vision loss for the past 20 years. He had bilateral hearing loss leading to deaf-mutism. In addition, his developmental milestones were delayed. His fundoscopic findings were consistent with RP and his electroretinography confirmed reduced retinal activity. Pure tone audiometry confirmed bilateral sensory neural hearing. His mother was a known case of Usher syndrome type 1. His family history was remarkable for multiple consanguineous marriages in both his parental and maternal families and a confirmed diagnosis of Usher syndrome in paternal uncle. The patient was tried on hearing aids and vitamin A medication but with minimal improvement in his overall condition. A multidisciplinary approach, involving an audiologist, speech, and language therapist was adapted to help the patient. Early genetic testing can help diagnose such cases in its early stages and genetic counseling regarding the detrimental effects of consanguineous marriages can play a very positive role in genetic diseases, especially those with autosomal recessive inheritance patterns.
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Affiliation(s)
- Ali I Awan
- Psychiatry and Behavioral Sciences, King Edward Medical University, Mayo Hospital, Lahore, PAK
| | | | - Ayesha Liaqat
- Internal Medicine, Services Institute of Medical Sciences, Lahore, PAK
| | - Taimoor Hassan
- Internal Medicine, District Headquarter Hospital, Nankana Sahib, PAK
| | - Maria Khan
- Internal Medicine, King Edward Medical University, Mayo Hospital, Lahore, PAK
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Aberrant Splicing Events Associated to CDH23 Noncanonical Splice Site Mutations in a Proband with Atypical Usher Syndrome 1. Genes (Basel) 2019; 10:genes10100732. [PMID: 31546658 PMCID: PMC6826400 DOI: 10.3390/genes10100732] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 09/17/2019] [Accepted: 09/19/2019] [Indexed: 12/16/2022] Open
Abstract
Aims: The aim of this study was the genetic diagnosis by next generation sequencing (NGS) of a patient diagnosed with Usher syndrome type 2 and the functional evaluation of the identified genetic variants to establish a phenotype–genotype correlation. Methods: Whole exome sequencing (WES) analysis identified two heterozygous intronic variants in CDH23, a gene responsible of Usher syndrome type 1. Evaluation of the putative splicing effects was performed in vivo, in whole blood samples, and in vitro, by transfection of midigene constructs in HEK293T cells. Results: Two intronic variants were identified in intron 45 of CDH23—one novel, c.6050-15G>A, and the other, c.6050-9G>A, already reported as a noncanonical splice site (NCSS) mutation—with partial functional characterization. In vivo and in vitro analyses showed aberrant transcripts by the addition of 13 and 7 nucleotides to exon 46, respectively. Transcript degradation by nonsense mediated decay (NMD) in blood cells could only be prevented by cycloheximide treatment. Midigene constructs showed that the two variants contributed to exon skipping and generated aberrantly spliced transcripts. Conclusions: A combination of in vivo and in vitro assays provided a comprehensive view of the physiological effects of NCSS variants, which in this case led to a clinical reassignment of the proband as affected with atypical USH1 syndrome.
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Abstract
OBJECTIVE PDZD7 was identified in 2009 in a family with apparent nonsyndromic sensorineural hearing loss. However, subsequent clinical reports have associated PDZD7 with digenic Usher syndrome, the most common cause of deaf-blindness, or as a modifier of retinal disease. No further reports have validated this gene for nonsyndromic hearing loss, intuitively calling correct genotype-phenotype association into question. This report describes a validating second case for biallelic mutations in PDZD7 causing nonsyndromic mild to severe sensorineural hearing loss. It also provides detailed audiometric and ophthalmologic data excluding Usher syndrome in both the present proband (proband 1) and the first proband described in 2009 (proband 2). DESIGN Proband 1 was sequenced using a custom-designed next generation sequencing panel consisting of 151 deafness genes. Bioinformatics analysis and filtering disclosed two PDZD7 sequence variants (c.1648C>T, p.Q550* and c.2107del, p.S703Vfs*20). Segregation testing followed in the family. For both probands, audiograms were collected and analyzed for progressive hearing loss and detailed ophthalmic evaluations were performed including electroretinography. RESULTS Proband 1 demonstrated a prelingual, nonsyndromic, sensorineural hearing loss that progressed in the higher frequencies between 4 and 9 years old. PDZD7 segregation analysis confirmed biallelic inheritance (compound heterozygosity). Mutation analysis determined the c.1648C>T mutation as novel and reported the c.2107del deletion as rs397516633 with a calculated minor allele frequency of 0.000018. Clinical evaluation spanning well over a decade in proband 2 disclosed bilateral, nonprogressive hearing loss. Both probands showed healthy retinas, excluding Usher syndrome-like changes in the eye. CONCLUSIONS PDZD7 is confirmed as a bona fide autosomal recessive nonsyndromic hearing loss gene. In both probands, there was no evidence of impaired vision or ophthalmic pathology. As the current understanding of PDZD7 mutations bridge Mendelian and complex phenotypes, the authors recommend careful variant interpretation, since PDZD7 is one of many genes associated with both Usher syndrome and autosomal recessive nonsyndromic hearing loss. Additional reports are required for understanding the complete phenotypic spectrum of this gene, including the possibility of high-frequency progression, as well as noise-induced hearing loss susceptibility in adult carriers. This report rules out all forms of Usher syndrome with an onset before 12 and 15 years old in probands 1 and 2, respectively. However, due to the young ages of the probands, this report is uninformative regarding older patients.
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Men CJ, Bujakowska KM, Comander J, Place E, Bedoukian EC, Zhu X, Leroy BP, Fulton AB, Pierce EA. The importance of genetic testing as demonstrated by two cases of CACNA1F-associated retinal generation misdiagnosed as LCA. Mol Vis 2017; 23:695-706. [PMID: 29062221 PMCID: PMC5640518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 10/08/2017] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To describe in detail cases with an initial diagnosis of Leber congenital amaurosis that were later found to have a hemizygous mutation in the CACNA1F gene. METHODS The patients underwent a detailed ophthalmological evaluation and full-field electroretinography (ERG). Selective targeted capture and whole-exome next-generation sequencing (NGS) were used to find the disease-causing mutations. RESULTS Patient 1 presented at age 3 months with nystagmus, normal visual attention, and a normal fundus exam. ERG responses were severely decreased. Patient 2 presented with nystagmus, severe hyperopia, esotropia, and visual acuity of 20/360 oculus dexter (OD) and 20/270 oculus sinister (OS) at age 5 months. His fundus exam showed slightly increased pigmentation around the foveae. The scotopic ERG responses were severely decreased and photopic responses mildly decreased. Based on the initial presentation, both patients received the clinical diagnosis of Leber congenital amaurosis (LCA). However, genetic testing showed no mutations in known LCA genes. Instead, broader genetic testing using NGS showed point mutations in the CACNA1F gene, which is reported to be associated with type 2 congenital stationary night blindness (CSNB2). CONCLUSIONS These two cases demonstrate the clinical overlap between LCA and CSNB in infants and young children. Genetic testing is an essential tool in these cases and provides a more accurate diagnosis and prognosis for patients with inherited retinal degenerative disorders.
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Affiliation(s)
- Clara J. Men
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA
| | - Kinga M. Bujakowska
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA
| | - Jason Comander
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA
| | - Emily Place
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA
| | - Emma C. Bedoukian
- Ophthalmic Genetics & Visual Electrophysiology, Division of Ophthalmology, The Children’s Hospital of Philadelphia, PA
| | - Xiaosong Zhu
- Ophthalmic Genetics & Visual Electrophysiology, Division of Ophthalmology, The Children’s Hospital of Philadelphia, PA
| | - Bart P. Leroy
- Ophthalmic Genetics & Visual Electrophysiology, Division of Ophthalmology, The Children’s Hospital of Philadelphia, PA,Department of Ophthalmology & Center for Medical Genetics, Ghent University Hospital & Ghent University, Ghent, Belgium
| | - Anne B. Fulton
- Department of Ophthalmology, Boston Children’s Hospital, Boston, MA
| | - Eric A. Pierce
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA
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Comander J, Weigel-DiFranco C, Maher M, Place E, Wan A, Harper S, Sandberg MA, Navarro-Gomez D, Pierce EA. The Genetic Basis of Pericentral Retinitis Pigmentosa-A Form of Mild Retinitis Pigmentosa. Genes (Basel) 2017; 8:genes8100256. [PMID: 28981474 PMCID: PMC5664106 DOI: 10.3390/genes8100256] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 09/06/2017] [Accepted: 09/19/2017] [Indexed: 12/25/2022] Open
Abstract
Pericentral retinitis pigmentosa (RP) is an atypical form of RP that affects the near-peripheral retina first and tends to spare the far periphery. This study was performed to further define the genetic basis of this phenotype. We identified a cohort of 43 probands with pericentral RP based on a comprehensive analysis of their retinal phenotype. Genetic analyses of DNA samples from these patients were performed using panel-based next-generation sequencing, copy number variations, and whole exome sequencing (WES). Mutations provisionally responsible for disease were found in 19 of the 43 families (44%) analyzed. These include mutations in RHO (five patients), USH2A (four patients), and PDE6B (two patients). Of 28 putatively pathogenic alleles, 15 (54%) have been previously identified in patients with more common forms of typical RP, while the remaining 13 mutations (46%) were novel. Burden testing of WES data successfully identified HGSNAT as a cause of pericentral RP in at least two patients, suggesting it is also a relatively common cause of pericentral RP. While additional sequencing might uncover new genes specifically associated with pericentral RP, the current results suggest that genetically pericentral RP is not a separate clinical entity, but rather is part of the spectrum of mild RP phenotypes.
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Affiliation(s)
- Jason Comander
- Ocular Genomics Institute, Berman-Gund Laboratory for the Study of Retinal Degenerations, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA.
| | - Carol Weigel-DiFranco
- Ocular Genomics Institute, Berman-Gund Laboratory for the Study of Retinal Degenerations, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA.
| | - Matthew Maher
- Ocular Genomics Institute, Berman-Gund Laboratory for the Study of Retinal Degenerations, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA.
| | - Emily Place
- Ocular Genomics Institute, Berman-Gund Laboratory for the Study of Retinal Degenerations, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA.
| | - Aliete Wan
- Ocular Genomics Institute, Berman-Gund Laboratory for the Study of Retinal Degenerations, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA.
| | - Shyana Harper
- Ocular Genomics Institute, Berman-Gund Laboratory for the Study of Retinal Degenerations, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA.
| | - Michael A Sandberg
- Ocular Genomics Institute, Berman-Gund Laboratory for the Study of Retinal Degenerations, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA.
| | - Daniel Navarro-Gomez
- Ocular Genomics Institute, Berman-Gund Laboratory for the Study of Retinal Degenerations, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA.
| | - Eric A Pierce
- Ocular Genomics Institute, Berman-Gund Laboratory for the Study of Retinal Degenerations, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA.
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Neuhaus C, Eisenberger T, Decker C, Nagl S, Blank C, Pfister M, Kennerknecht I, Müller-Hofstede C, Charbel Issa P, Heller R, Beck B, Rüther K, Mitter D, Rohrschneider K, Steinhauer U, Korbmacher HM, Huhle D, Elsayed SM, Taha HM, Baig SM, Stöhr H, Preising M, Markus S, Moeller F, Lorenz B, Nagel-Wolfrum K, Khan AO, Bolz HJ. Next-generation sequencing reveals the mutational landscape of clinically diagnosed Usher syndrome: copy number variations, phenocopies, a predominant target for translational read-through, and PEX26 mutated in Heimler syndrome. Mol Genet Genomic Med 2017; 5:531-552. [PMID: 28944237 PMCID: PMC5606877 DOI: 10.1002/mgg3.312] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 06/06/2017] [Accepted: 06/09/2017] [Indexed: 12/23/2022] Open
Abstract
Background Combined retinal degeneration and sensorineural hearing impairment is mostly due to autosomal recessive Usher syndrome (USH1: congenital deafness, early retinitis pigmentosa (RP); USH2: progressive hearing impairment, RP). Methods Sanger sequencing and NGS of 112 genes (Usher syndrome, nonsyndromic deafness, overlapping conditions), MLPA, and array‐CGH were conducted in 138 patients clinically diagnosed with Usher syndrome. Results A molecular diagnosis was achieved in 97% of both USH1 and USH2 patients, with biallelic mutations in 97% (USH1) and 90% (USH2), respectively. Quantitative readout reliably detected CNVs (confirmed by MLPA or array‐CGH), qualifying targeted NGS as one tool for detecting point mutations and CNVs. CNVs accounted for 10% of identified USH2A alleles, often in trans to seemingly monoallelic point mutations. We demonstrate PTC124‐induced read‐through of the common p.Trp3955* nonsense mutation (13% of detected USH2A alleles), a potential therapy target. Usher gene mutations were found in most patients with atypical Usher syndrome, but the diagnosis was adjusted in case of double homozygosity for mutations in OTOA and NR2E3, genes implicated in isolated deafness and RP. Two patients with additional enamel dysplasia had biallelic PEX26 mutations, for the first time linking this gene to Heimler syndrome. Conclusion Targeted NGS not restricted to Usher genes proved beneficial in uncovering conditions mimicking Usher syndrome.
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Affiliation(s)
| | | | | | - Sandra Nagl
- Bioscientia Center for Human GeneticsIngelheimGermany
| | | | - Markus Pfister
- HNO-Praxis SarnenSarnenSwitzerland.,Molecular Genetics, THRCDepartment of OtolaryngologyUniversity of TübingenTübingenGermany
| | - Ingo Kennerknecht
- Institute of Human GeneticsWestfälische Wilhelms-UniversitätMünsterGermany
| | | | - Peter Charbel Issa
- Department of OphthalmologyUniversity of BonnBonnGermany.,Center for Rare Diseases Bonn (ZSEB)University of BonnBonnGermany.,Oxford Eye HospitalUniversity of OxfordOxfordUK
| | - Raoul Heller
- Institute of Human GeneticsUniversity Hospital of CologneCologneGermany
| | - Bodo Beck
- Institute of Human GeneticsUniversity Hospital of CologneCologneGermany
| | | | - Diana Mitter
- Institute of Human GeneticsUniversity of Leipzig Hospitals and ClinicsLeipzigGermany
| | | | | | - Heike M Korbmacher
- Department of OrthodonticsGiessen and Marburg University Hospital, Marburg CampusMarburgGermany
| | | | - Solaf M Elsayed
- Medical Genetics CenterCairoEgypt.,Children's HospitalAin Shams UniversityCairoEgypt
| | | | - Shahid M Baig
- Human Molecular Genetics LaboratoryHealth Biotechnology DivisionNational Institute for Biotechnology and Genetic Engineering (NIBGE)FaisalabadPakistan
| | - Heidi Stöhr
- Department of Human GeneticsUniversity Medical Center RegensburgRegensburgGermany
| | - Markus Preising
- Department of OphthalmologyJustus-Liebig-University GiessenGiessenGermany
| | | | - Fabian Moeller
- Department of Cell and Matrix BiologyInstitute of Zoology, Johannes GutenbergUniversity of MainzMainzGermany
| | - Birgit Lorenz
- Department of OphthalmologyJustus-Liebig-University GiessenGiessenGermany
| | - Kerstin Nagel-Wolfrum
- Department of Cell and Matrix BiologyInstitute of Zoology, Johannes GutenbergUniversity of MainzMainzGermany
| | - Arif O Khan
- Division of Pediatric OphthalmologyKing Khaled Eye Specialist HospitalRiyadhSaudi Arabia.,Eye InstituteCleveland ClinicAbu DhabiUAE
| | - Hanno J Bolz
- Bioscientia Center for Human GeneticsIngelheimGermany.,Institute of Human GeneticsUniversity Hospital of CologneCologneGermany
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Ung C, Sanchez AV, Shen L, Davoudi S, Ahmadi T, Navarro-Gomez D, Chen CJ, Hancock H, Penman A, Hoadley S, Consugar M, Restrepo C, Shah VA, Arboleda-Velasquez JF, Sobrin L, Gai X, Kim LA. Whole exome sequencing identification of novel candidate genes in patients with proliferative diabetic retinopathy. Vision Res 2017; 139:168-176. [PMID: 28431867 DOI: 10.1016/j.visres.2017.03.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 03/28/2017] [Accepted: 03/30/2017] [Indexed: 10/19/2022]
Abstract
Rare or novel gene variants in patients with proliferative diabetic retinopathy may contribute to disease development. We performed whole exome sequencing (WES) on patients at the phenotypic extremes of diabetic retinal complications: 57 patients diagnosed with proliferative diabetic retinopathy (PDR) as cases and 13 patients with no diabetic retinopathy despite at least 10years of type 2 diabetes as controls. Thirty-one out of the 57 cases and all 13 controls were from the African American Proliferative Diabetic Retinopathy Study (AA). The rest of the cases were of mixed ethnicities (ME). WES identified 721 candidate genes with rare or novel non-synonymous variants found in at least one case with PDR and not present in any controls. After filtering for genes with null alleles in greater than two cases, 28 candidate genes were identified in our ME cases and 16 genes were identified in our AA cases. Our analysis showed rare and novel variants within these genes that could contribute to the development of PDR, including rare non-synonymous variants in FAM132A, SLC5A9, ZNF600, and TMEM217. We also found previously unidentified variants in VEGFB and APOB. We found that VEGFB, VPS13B, PHF21A, NAT1, ZNF600, PKHD1L1 expression was reduced in human retinal endothelial cells (HRECs) cultured under high glucose conditions. In an exome sequence analysis of patients with PDR, we identified variants in genes that could contribute to pathogenesis. Six of these genes were further validated and found to have reduced expression in HRECs under high glucose conditions, suggestive of an important role in the development of PDR.
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Affiliation(s)
- Cindy Ung
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Angie V Sanchez
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Lishuang Shen
- Center for Personalized Medicine, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Samaneh Davoudi
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Tina Ahmadi
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Daniel Navarro-Gomez
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Ching J Chen
- Department of Ophthalmology, University of Mississippi Medical Center, Jackson, MS, USA
| | - Heather Hancock
- Department of Ophthalmology, University of Mississippi Medical Center, Jackson, MS, USA
| | - Alan Penman
- Department of Medicine, University of Mississippi Medical Center, Jackson, MS, USA
| | - Suzanne Hoadley
- Department of Ophthalmology, University of Mississippi Medical Center, Jackson, MS, USA
| | - Mark Consugar
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Carlos Restrepo
- Basic Science Group, School of Medicine, CES University, Medellin, Colombia
| | - Vinay A Shah
- Department of Ophthalmology, Dean McGee Eye Institute, University of Oklahoma, OK, USA
| | - Joseph F Arboleda-Velasquez
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.
| | - Lucia Sobrin
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA.
| | - Xiaowu Gai
- Center for Personalized Medicine, Children's Hospital Los Angeles, Los Angeles, CA, USA.
| | - Leo A Kim
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA.
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11
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Kletke S, Batmanabane V, Dai T, Vincent A, Li S, Gordon KA, Papsin BC, Cushing SL, Héon E. The combination of vestibular impairment and congenital sensorineural hearing loss predisposes patients to ocular anomalies, including Usher syndrome. Clin Genet 2017; 92:26-33. [PMID: 27743452 DOI: 10.1111/cge.12895] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 10/05/2016] [Accepted: 10/12/2016] [Indexed: 11/29/2022]
Abstract
The co-occurrence of hearing impairment and visual dysfunction is devastating. Most deaf-blind etiologies are genetically determined, the commonest being Usher syndrome (USH). While studies of the congenitally deaf population reveal a variable degree of visual problems, there are no effective ophthalmic screening guidelines. We hypothesized that children with congenital sensorineural hearing loss (SNHL) and vestibular impairment were at an increased risk of having USH. A retrospective chart review of 33 cochlear implants recipients for severe to profound SNHL and measured vestibular dysfunction was performed to determine the ocular phenotype. All the cases had undergone ocular examination and electroretinogram (ERG). Patients with an abnormal ERG underwent genetic testing for USH. We found an underlying ocular abnormality in 81.81% (27/33) of cases; of which 75% had refractive errors, and 50% of those patients showed visual improvement with refractive correction. A total of 14 cases (42.42%; 14/33) had generalized rod-cone dysfunction on ERG suggestive of Usher syndrome type 1, confirmed by mutational analysis. This work shows that adding vestibular impairment as a criterion for requesting an eye exam and adding the ERG to detect USH increases the chances of detecting ocular anomalies, when compared with previous literature focusing only on congenital SNHL.
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Affiliation(s)
- S Kletke
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
| | - V Batmanabane
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - T Dai
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
| | - A Vincent
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada.,Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - S Li
- Program of Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - K A Gordon
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada.,Department of Otolaryngology - Head & Neck Surgery, The Hospital for Sick Children, Toronto, Ontario, Canada.,Archie's Cochlear Implant Laboratory, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - B C Papsin
- Department of Otolaryngology - Head & Neck Surgery, The Hospital for Sick Children, Toronto, Ontario, Canada.,Archie's Cochlear Implant Laboratory, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - S L Cushing
- Department of Otolaryngology - Head & Neck Surgery, The Hospital for Sick Children, Toronto, Ontario, Canada.,Archie's Cochlear Implant Laboratory, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - E Héon
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada.,Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Ontario, Canada.,Program of Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Ontario, Canada
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12
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An innovative strategy for the molecular diagnosis of Usher syndrome identifies causal biallelic mutations in 93% of European patients. Eur J Hum Genet 2016; 24:1730-1738. [PMID: 27460420 PMCID: PMC5117943 DOI: 10.1038/ejhg.2016.99] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 05/23/2016] [Accepted: 06/04/2016] [Indexed: 11/08/2022] Open
Abstract
Usher syndrome (USH), the most prevalent cause of hereditary deafness–blindness, is an autosomal recessive and genetically heterogeneous disorder. Three clinical subtypes (USH1–3) are distinguishable based on the severity of the sensorineural hearing impairment, the presence or absence of vestibular dysfunction, and the age of onset of the retinitis pigmentosa. A total of 10 causal genes, 6 for USH1, 3 for USH2, and 1 for USH3, and an USH2 modifier gene, have been identified. A robust molecular diagnosis is required not only to improve genetic counseling, but also to advance gene therapy in USH patients. Here, we present an improved diagnostic strategy that is both cost- and time-effective. It relies on the sequential use of three different techniques to analyze selected genomic regions: targeted exome sequencing, comparative genome hybridization, and quantitative exon amplification. We screened a large cohort of 427 patients (139 USH1, 282 USH2, and six of undefined clinical subtype) from various European medical centers for mutations in all USH genes and the modifier gene. We identified a total of 421 different sequence variants predicted to be pathogenic, about half of which had not been previously reported. Remarkably, we detected large genomic rearrangements, most of which were novel and unique, in 9% of the patients. Thus, our strategy led to the identification of biallelic and monoallelic mutations in 92.7% and 5.8% of the USH patients, respectively. With an overall 98.5% mutation characterization rate, the diagnosis efficiency was substantially improved compared with previously reported methods.
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13
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Ben-Rebeh I, Grati M, Bonnet C, Bouassida W, Hadjamor I, Ayadi H, Ghorbel A, Petit C, Masmoudi S. Genetic analysis of Tunisian families with Usher syndrome type 1: toward improving early molecular diagnosis. Mol Vis 2016; 22:827-35. [PMID: 27440999 PMCID: PMC4950652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 07/16/2016] [Indexed: 10/26/2022] Open
Abstract
PURPOSE Usher syndrome accounts for about 50% of all hereditary deaf-blindness cases. The most severe form of this syndrome, Usher syndrome type I (USH1), is characterized by profound congenital sensorineural deafness, vestibular dysfunction, and retinitis pigmentosa. Six USH1 genes have been identified, MYO7A, CDH23, PCDH15, USH1C, SANS, and CIB2, encoding myosin VIIA, cadherin-23, protocadherin-15, harmonin, scaffold protein containing ankyrin repeats and a sterile alpha motif (SAM) domain, and calcium- and integrin-binding member 2, respectively. METHODS In the present study, we recruited four Tunisian families with a diagnosis of USH1, together with healthy unrelated controls. Affected members underwent detailed audiologic and ocular examinations. We used the North African Deafness (NADf) chip to search for known North African mutations associated with USH. Then, we selected microsatellite markers covering USH1 known loci to genotype the DNA samples. Finally, we performed DNA sequencing of three known USH1 genes: MYO7A, PCDH15, and USH1C. RESULTS Four biallelic mutations, all single base changes, were found in the MYO7A, USH1C, and PCDH15 genes. These mutations consist of a previously reported splicing defect c.470+1G>A in MYO7A, three novel variants, including two nonsense (p.Arg3X and p.Arg134X) in USH1C and PCDH15, respectively, and one frameshift (p.Lys615Asnfs*6) in MYO7A. CONCLUSIONS We found a remarkable genetic heterogeneity in the studied families with USH1 with a variety of mutations, among which three were novel. These novel mutations will be included in the NADf mutation screening chip that will allow a higher diagnosis efficiency of this extremely genetically heterogeneous disease. Ultimately, efficient molecular diagnosis of USH in a patient's early childhood is of utmost importance, allowing better educational and therapeutic management.
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Affiliation(s)
- Imen Ben-Rebeh
- Laboratoire de Procédés de criblage moléculaire et cellulaire, Centre de Biotechnologie de Sfax, Université de Sfax, Tunisie
| | - Mhamed Grati
- Unité de Génétique et Physiologie de l'Audition, INSERM UMRS 1120, Institut Pasteur, Paris, France
| | | | - Walid Bouassida
- Service d'Ophtalmologie, C.H.U. H. Bourguiba de Sfax, Tunisie
| | - Imen Hadjamor
- Laboratoire de Procédés de criblage moléculaire et cellulaire, Centre de Biotechnologie de Sfax, Université de Sfax, Tunisie
| | - Hammadi Ayadi
- Laboratoire de Procédés de criblage moléculaire et cellulaire, Centre de Biotechnologie de Sfax, Université de Sfax, Tunisie
| | | | - Christine Petit
- Unité de Génétique et Physiologie de l'Audition, INSERM UMRS 1120, Institut Pasteur, Paris, France; INSERM UMRS 1120, Institut de la Vision, Paris, France; Collège de France, Paris, France
| | - Saber Masmoudi
- Laboratoire de Procédés de criblage moléculaire et cellulaire, Centre de Biotechnologie de Sfax, Université de Sfax, Tunisie
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14
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Bujakowska KM, White J, Place E, Consugar M, Comander J. Efficient In Silico Identification of a Common Insertion in the MAK Gene which Causes Retinitis Pigmentosa. PLoS One 2015; 10:e0142614. [PMID: 26558903 PMCID: PMC4641726 DOI: 10.1371/journal.pone.0142614] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Accepted: 10/23/2015] [Indexed: 11/19/2022] Open
Abstract
Background Next generation sequencing (NGS) offers a rapid and comprehensive method of screening for mutations associated with retinitis pigmentosa and related disorders. However, certain sequence alterations such as large insertions or deletions may remain undetected using standard NGS pipelines. One such mutation is a recently-identified Alu insertion into the Male Germ Cell-Associated Kinase (MAK) gene, which is missed by standard NGS-based variant callers. Here, we developed an in silico method of searching NGS raw sequence reads to detect this mutation, without the need to recalculate sequence alignments or to screen every sample by PCR. Methods The Linux program grep was used to search for a 23 bp “probe” sequence containing the known junction sequence of the insert. A corresponding search was performed with the wildtype sequence. The matching reads were counted and further compared to the known sequences of the full wildtype and mutant genomic loci. (See https://github.com/MEEIBioinformaticsCenter/grepsearch.) Results In a test sample set consisting of eleven previously published homozygous mutants, detection of the MAK-Alu insertion was validated with 100% sensitivity and specificity. As a discovery cohort, raw NGS reads from 1,847 samples (including custom and whole exome selective capture) were searched in ~1 hour on a local computer cluster, yielding an additional five samples with MAK-Alu insertions and solving two previously unsolved pedigrees. Of these, one patient was homozygous for the insertion, one compound heterozygous with a missense change on the other allele (c. 46G>A; p.Gly16Arg), and three were heterozygous carriers. Conclusions Using the MAK-Alu grep program proved to be a rapid and effective method of finding a known, disease-causing Alu insertion in a large cohort of patients with NGS data. This simple approach avoids wet-lab assays or computationally expensive algorithms, and could also be used for other known disease-causing insertions and deletions.
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Affiliation(s)
- Kinga M. Bujakowska
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Joseph White
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Emily Place
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Mark Consugar
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Jason Comander
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
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15
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Yang L, Cui H, Yin X, Dou H, Zhao L, Chen N, Zhang J, Zhang H, Li G, Ma Z. Dependable and Efficient Clinical Molecular Diagnosis of Chinese RP Patient with Targeted Exon Sequencing. PLoS One 2015; 10:e0140684. [PMID: 26496393 PMCID: PMC4619688 DOI: 10.1371/journal.pone.0140684] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 09/29/2015] [Indexed: 11/28/2022] Open
Abstract
Retinitis pigmentosa (RP) is the most common inherited retinal disease. It is a clinically and genetically heterogeneous disorder, which is why it is particularly challenging to diagnose. The aim of this study was to establish a targeted next-generation sequencing (NGS) approach for the comprehensive, rapid, and cost-effective clinical molecular diagnosis of RP. A specific hereditary eye disease enrichment panel (HEDEP) based on exome capture technology was used to collect the protein coding regions of 371 targeted hereditary eye disease genes, followed by high-throughput sequencing on the Illumina HiSeq2000 platform. From a cohort of 34 Chinese RP families, 13 families were successfully diagnosed; thus, the method achieves a diagnostic rate of approximately 40%. Of 16 pathogenic mutations identified, 11 were novel. Our study demonstrates that targeted capture sequencing offers a rapid and effective method for the molecular diagnosis of RP, which helps to provide a more accurate clinical diagnosis and paves the way for genetic counseling, family planning, and future gene-targeted treatment.
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Affiliation(s)
- Liping Yang
- Department of Ophthalmology, Peking University Third Hospital, Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing, P. R. China
| | - Hui Cui
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, P. R. China
| | - Xiaobei Yin
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, P. R. China
| | - Hongliang Dou
- Department of Ophthalmology, Peking University Third Hospital, Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing, P. R. China
| | - Lin Zhao
- Department of Ophthalmology, Peking University Third Hospital, Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing, P. R. China
| | - Ningning Chen
- Department of Ophthalmology, Peking University Third Hospital, Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing, P. R. China
| | - Jinlu Zhang
- Department of Ophthalmology, Peking University Third Hospital, Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing, P. R. China
| | - Huirong Zhang
- Department of Ophthalmology, Peking University Third Hospital, Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing, P. R. China
| | - Genlin Li
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, P. R. China
- * E-mail: (ZM); (GL)
| | - Zhizhong Ma
- Department of Ophthalmology, Peking University Third Hospital, Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing, P. R. China
- * E-mail: (ZM); (GL)
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16
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Abstract
Hearing loss (HL) is one of the most common birth defects in developed countries and is a diverse pathologic condition with different classifications. One of these is based on the association with other clinical features, defined as syndromic hearing loss (SHL). Determining the cause of the HL in these patients is extremely beneficial as it enables a personalized approach to caring for the individual. Early screening can further aid in optimal rehabilitation for a child's development and growth. The advancement of high-throughput sequencing technology is facilitating rapid and low-cost diagnostics for patients with SHL.
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Affiliation(s)
- Tal Koffler
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Kathy Ushakov
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Karen B Avraham
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel.
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