1
|
Gelernter J, Levey DF, Galimberti M, Harrington K, Zhou H, Adhikari K, Gupta P, Gaziano JM, Eliott D, Stein MB. Genome-wide association study of the common retinal disorder epiretinal membrane: Significant risk loci in each of three American populations. CELL GENOMICS 2024; 4:100582. [PMID: 38870908 DOI: 10.1016/j.xgen.2024.100582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 02/20/2024] [Accepted: 05/10/2024] [Indexed: 06/15/2024]
Abstract
Epiretinal membrane (ERM) is a common retinal condition characterized by the presence of fibrocellular tissue on the retinal surface, often with visual distortion and loss of visual acuity. We studied European American (EUR), African American (AFR), and Latino (admixed American, AMR) ERM participants in the Million Veteran Program (MVP) for genome-wide association analysis-a total of 38,232 case individuals and 557,988 control individuals. We completed a genome-wide association study (GWAS) in each population separately, and then results were meta-analyzed. Genome-wide significant (GWS) associations were observed in all three populations studied: 31 risk loci in EUR subjects, 3 in AFR, and 2 in AMR, with 48 in trans-ancestry meta-analysis. Many results replicated in the FinnGen sample. Several GWS variants associate to alterations in gene expression in the macula. ERM showed significant genetic correlation to multiple traits. Pathway enrichment analyses implicated collagen and collagen-adjacent mechanisms, among others. This well-powered ERM GWAS identified novel genetic associations that point to biological mechanisms for ERM.
Collapse
Affiliation(s)
- Joel Gelernter
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA; Department of Psychiatry, VA Connecticut Healthcare Center, West Haven, CT, USA; Departments of Genetics and Neuroscience, Yale School of Medicine, New Haven, CT, USA.
| | - Daniel F Levey
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA; Department of Psychiatry, VA Connecticut Healthcare Center, West Haven, CT, USA
| | - Marco Galimberti
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA; Department of Psychiatry, VA Connecticut Healthcare Center, West Haven, CT, USA
| | - Kelly Harrington
- Massachusetts Veterans Epidemiology Research and Information Center (MAVERIC), VA Boston Healthcare System, Boston, MA, USA; Department of Psychiatry, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, USA
| | - Hang Zhou
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA; Department of Psychiatry, VA Connecticut Healthcare Center, West Haven, CT, USA
| | - Keyrun Adhikari
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA; Department of Psychiatry, VA Connecticut Healthcare Center, West Haven, CT, USA
| | - Priya Gupta
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA; Department of Psychiatry, VA Connecticut Healthcare Center, West Haven, CT, USA
| | - J Michael Gaziano
- Department of Medicine, Harvard Medical School, Boston, MA, USA; Department of Medicine, Divisions of Aging and Preventative Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Dean Eliott
- Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Murray B Stein
- University of California, San Diego, La Jolla, CA, USA; VA San Diego Healthcare System, San Diego, CA, USA
| |
Collapse
|
2
|
Anselmi C, Fuller GK, Stolfi A, Groves AK, Manni L. Sensory cells in tunicates: insights into mechanoreceptor evolution. Front Cell Dev Biol 2024; 12:1359207. [PMID: 38550380 PMCID: PMC10973136 DOI: 10.3389/fcell.2024.1359207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 03/04/2024] [Indexed: 04/04/2024] Open
Abstract
Tunicates, the sister group of vertebrates, offer a unique perspective for evolutionary developmental studies (Evo-Devo) due to their simple anatomical organization. Moreover, the separation of tunicates from vertebrates predated the vertebrate-specific genome duplications. As adults, they include both sessile and pelagic species, with very limited mobility requirements related mainly to water filtration. In sessile species, larvae exhibit simple swimming behaviors that are required for the selection of a suitable substrate on which to metamorphose. Despite their apparent simplicity, tunicates display a variety of mechanoreceptor structures involving both primary and secondary sensory cells (i.e., coronal sensory cells). This review encapsulates two decades of research on tunicate mechanoreception focusing on the coronal organ's sensory cells as prime candidates for understanding the evolution of vertebrate hair cells of the inner ear and the lateral line organ. The review spans anatomical, cellular and molecular levels emphasizing both similarity and differences between tunicate and vertebrate mechanoreception strategies. The evolutionary significance of mechanoreception is discussed within the broader context of Evo-Devo studies, shedding light on the intricate pathways that have shaped the sensory system in chordates.
Collapse
Affiliation(s)
- Chiara Anselmi
- Hopkins Marine Station, Institute for Stem Cell Biology and Regenerative Medicine, Stanford University, Pacific Grove, CA, United States
- Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA, United States
| | - Gwynna K. Fuller
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Alberto Stolfi
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, United States
| | - Andrew K. Groves
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, United States
| | - Lucia Manni
- Dipartimento di Biologia, Università degli Studi di Padova, Padova, Italy
| |
Collapse
|
3
|
Munir A, Afsar S, Rehman AU. A systematic review of inherited retinal dystrophies in Pakistan: updates from 1999 to April 2023. BMC Ophthalmol 2024; 24:55. [PMID: 38317096 PMCID: PMC10840256 DOI: 10.1186/s12886-024-03319-7] [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: 06/01/2023] [Accepted: 01/19/2024] [Indexed: 02/07/2024] Open
Abstract
BACKGROUND Inherited retinal degenerations (IRDs) are a group of rare genetic conditions affecting retina of the eye that range in prevalence from 1 in 2000 to 1 in 4000 people globally. This review is based on a retrospective analysis of research articles reporting IRDs associated genetic findings in Pakistani families between 1999 and April 2023. METHODS Articles were retrieved through survey of online sources, notably, PubMed, Google Scholar, and Web of Science. Following a stringent selection criterion, a total of 126 research articles and conference abstracts were considered. All reported variants were cross-checked and validated for their correct genomic nomenclature using different online resources/databases, and their pathogenicity scores were explained as per ACMG guidelines. RESULTS A total of 277 unique sequence variants in 87 distinct genes, previously known to cause IRDs, were uncovered. In around 70% cases, parents of the index patient were consanguineously married, and approximately 88.81% of the detected variants were found in a homozygous state. Overall, more than 95% of the IRDs cases were recessively inherited. Missense variants were predominant (41.88%), followed by Indels/frameshift (26.35%), nonsense (19.13%), splice site (12.27%) and synonymous change (0.36%). Non-syndromic IRDs were significantly higher than syndromic IRDs (77.32% vs. 22.68%). Retinitis pigmentosa (RP) was the most frequently observed IRD followed by Leber's congenital amaurosis (LCA). Altogether, mutations in PDE6A gene was the leading cause of IRDs in Pakistani families followed by mutations in TULP1 gene. CONCLUSION In summary, Pakistani families are notable in expressing recessively inherited monogenic disorders including IRDs likely due to the highest prevalence of consanguinity in the country that leads to expression of rare pathogenic variants in homozygous state.
Collapse
Affiliation(s)
- Asad Munir
- Department of Zoology, Faculty of Biological and Health Sciences, Hazara University, Mansehra, 21300, Khyber Pakhtunkhwa, Pakistan
| | - Salma Afsar
- Department of Zoology, Faculty of Biological and Health Sciences, Hazara University, Mansehra, 21300, Khyber Pakhtunkhwa, Pakistan
| | - Atta Ur Rehman
- Department of Zoology, Faculty of Biological and Health Sciences, Hazara University, Mansehra, 21300, Khyber Pakhtunkhwa, Pakistan.
| |
Collapse
|
4
|
Holló A, Billington N, Takagi Y, Kengyel A, Sellers JR, Liu R. Molecular regulatory mechanism of human myosin-7a. J Biol Chem 2023; 299:105243. [PMID: 37690683 PMCID: PMC10579538 DOI: 10.1016/j.jbc.2023.105243] [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: 06/23/2023] [Revised: 09/01/2023] [Accepted: 09/04/2023] [Indexed: 09/12/2023] Open
Abstract
Myosin-7a is an actin-based motor protein essential for vision and hearing. Mutations of myosin-7a cause type 1 Usher syndrome, the most common and severe form of deafblindness in humans. The molecular mechanisms that govern its mechanochemistry remain poorly understood, primarily because of the difficulty of purifying stable intact protein. Here, we recombinantly produce the complete human myosin-7a holoenzyme in insect cells and characterize its biochemical and motile properties. Unlike the Drosophila ortholog that primarily associates with calmodulin (CaM), we found that human myosin-7a utilizes a unique combination of light chains including regulatory light chain, CaM, and CaM-like protein 4. Our results further reveal that CaM-like protein 4 does not function as a Ca2+ sensor but plays a crucial role in maintaining the lever arm's structural-functional integrity. Using our recombinant protein system, we purified two myosin-7a splicing isoforms that have been shown to be differentially expressed along the cochlear tonotopic axis. We show that they possess distinct mechanoenzymatic properties despite differing by only 11 amino acids at their N termini. Using single-molecule in vitro motility assays, we demonstrate that human myosin-7a exists as an autoinhibited monomer and can move processively along actin when artificially dimerized or bound to cargo adaptor proteins. These results suggest that myosin-7a can serve multiple roles in sensory systems such as acting as a transporter or an anchor/force sensor. Furthermore, our research highlights that human myosin-7a has evolved unique regulatory elements that enable precise tuning of its mechanical properties suitable for mammalian auditory functions.
Collapse
Affiliation(s)
- Alexandra Holló
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA; Department of Biophysics, University of Pécs Medical School, Pécs, Hungary
| | - Neil Billington
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA; Department of Biochemistry & Molecular Medicine, School of Medicine, West Virginia University, Morgantown, West Virginia, USA; Microscope Imaging Facility, West Virginia University, Morgantown, West Virginia, USA
| | - Yasuharu Takagi
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - András Kengyel
- Department of Biophysics, University of Pécs Medical School, Pécs, Hungary; Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - James R Sellers
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA.
| | - Rong Liu
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA; Department of Biochemistry & Molecular Medicine, School of Medicine, West Virginia University, Morgantown, West Virginia, USA.
| |
Collapse
|
5
|
Dubey AK, Mostafavi E. Biomaterials-mediated CRISPR/Cas9 delivery: recent challenges and opportunities in gene therapy. Front Chem 2023; 11:1259435. [PMID: 37841202 PMCID: PMC10568484 DOI: 10.3389/fchem.2023.1259435] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Accepted: 09/15/2023] [Indexed: 10/17/2023] Open
Abstract
The use of biomaterials in delivering CRISPR/Cas9 for gene therapy in infectious diseases holds tremendous potential. This innovative approach combines the advantages of CRISPR/Cas9 with the protective properties of biomaterials, enabling accurate and efficient gene editing while enhancing safety. Biomaterials play a vital role in shielding CRISPR/Cas9 components, such as lipid nanoparticles or viral vectors, from immunological processes and degradation, extending their effectiveness. By utilizing the flexibility of biomaterials, tailored systems can be designed to address specific genetic diseases, paving the way for personalized therapeutics. Furthermore, this delivery method offers promising avenues in combating viral illnesses by precisely modifying pathogen genomes, and reducing their pathogenicity. Biomaterials facilitate site-specific gene modifications, ensuring effective delivery to infected cells while minimizing off-target effects. However, challenges remain, including optimizing delivery efficiency, reducing off-target effects, ensuring long-term safety, and establishing scalable production techniques. Thorough research, pre-clinical investigations, and rigorous safety evaluations are imperative for successful translation from the laboratory to clinical applications. In this review, we discussed how CRISPR/Cas9 delivery using biomaterials revolutionizes gene therapy and infectious disease treatment, offering precise and safe editing capabilities with the potential to significantly improve human health and quality of life.
Collapse
Affiliation(s)
- Ankit Kumar Dubey
- Global Research and Publishing Foundation, New Delhi, India
- Institute of Scholars, Bengaluru, Karnataka, India
| | - Ebrahim Mostafavi
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, United States
- Department of Medicine, Stanford University School of Medicine, Stanford, CA, United States
| |
Collapse
|
6
|
Filson MJ, Davis DC, Yother C. Clinical Presentation of Usher Syndrome Type 1B (USH1B) in a 10-Month-Old: A Case Report. Cureus 2023; 15:e43934. [PMID: 37746462 PMCID: PMC10513348 DOI: 10.7759/cureus.43934] [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: 04/07/2023] [Accepted: 08/22/2023] [Indexed: 09/26/2023] Open
Abstract
Usher Syndrome (USH) is a genetically inherited condition characterized by congenital sensorineural hearing loss and progressive vision loss secondary to retinitis pigmentosa. Patients may also display vestibular areflexia and balance issues secondary to inner ear damage. Usher Syndrome is the most commonly diagnosed syndrome within the blind-deaf community, and it accounts for a significant portion of the hearing and visual deficit cases among patients younger than 65 years of age. Due to the reported prevalence of Usher Syndrome in the United States, it appears there is chronic underdiagnosis in clinical settings throughout the country. A possible explanation for this is the visual deficits of Usher syndrome do not appear until later in life and thus inappropriately lower the index of suspicion for this diagnosis in young children with hearing deficits. This case study highlights a healthy newborn who failed the universal newborn hearing screening (UNHS) bilaterally and a follow-up hearing screening in a pediatrician's office. Auditory brainstem response (ABR) later confirmed bilateral severe-to-profound sensorineural hearing loss. Upon genetic testing, an abnormality in the Unconventional Myosin VII-A (MYO7) gene was discovered and consistent with Usher syndrome Type 1B (USH1B). Usher Syndrome should be considered on the differential for patients with congenital hearing loss. Genetic counseling should be used if no other cause of sensorineural hearing loss is identified. Due to the progressive nature of this condition and the physical and developmental deficits that will transpire without treatment, a genetic panel for hearing loss should be prioritized to determine the presence of genetic mutations suggesting Usher syndrome.
Collapse
Affiliation(s)
- Meghan J Filson
- Medicine, Edward Via College of Osteopathic Medicine, Auburn, USA
| | - Dakota C Davis
- Medicine, Alabama College of Osteopathic Medicine, Dothan, USA
| | - Claire Yother
- Pediatrics, Gadsden Pediatric Clinic, P.A., Gadsden, USA
| |
Collapse
|
7
|
Stanley OR, Swaminathan A, Wojahn E, Ahmed ZM, Cullen KE. An Open-Source Tool for Automated Human-Level Circling Behavior Detection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.30.540066. [PMID: 37398316 PMCID: PMC10312579 DOI: 10.1101/2023.05.30.540066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Quantifying behavior and relating it to underlying biological states is of paramount importance in many life science fields. Although barriers to recording postural data have been reduced by progress in deep-learning-based computer vision tools for keypoint tracking, extracting specific behaviors from this data remains challenging. Manual behavior coding, the present gold standard, is labor-intensive and subject to intra- and inter-observer variability. Automatic methods are stymied by the difficulty of explicitly defining complex behaviors, even ones which appear obvious to the human eye. Here, we demonstrate an effective technique for detecting one such behavior, a form of locomotion characterized by stereotyped spinning, termed 'circling'. Though circling has an extensive history as a behavioral marker, at present there exists no standard automated detection method. Accordingly, we developed a technique to identify instances of the behavior by applying simple postprocessing to markerless keypoint data from videos of freely-exploring (Cib2-/-;Cib3-/-) mutant mice, a strain we previously found to exhibit circling. Our technique agrees with human consensus at the same level as do individual observers, and it achieves >90% accuracy in discriminating videos of wild type mice from videos of mutants. As using this technique requires no experience writing or modifying code, it also provides a convenient, noninvasive, quantitative tool for analyzing circling mouse models. Additionally, as our approach was agnostic to the underlying behavior, these results support the feasibility of algorithmically detecting specific, research-relevant behaviors using readily-interpretable parameters tuned on the basis of human consensus.
Collapse
Affiliation(s)
- O R Stanley
- Dept. Biomedical Engineering; Johns Hopkins University
| | - A Swaminathan
- Dept. Biomedical Engineering; Johns Hopkins University
| | - E Wojahn
- Dept. Biomedical Engineering; Johns Hopkins University
| | - Z M Ahmed
- Depts. Otorhinolaryngology-Head & Neck Surgery, Biochemistry & Molecular Biology, Ophthalmology; University of Maryland School of Medicine
| | - K E Cullen
- Dept. Biomedical Engineering; Johns Hopkins University
- Depts. Neuroscience, Otolaryngology-Head & Neck Surgery, Johns Hopkins University
| |
Collapse
|
8
|
Ordoñez-Labastida V, Chacon-Camacho OF, Lopez-Rodriguez VR, Zenteno JC. USH2A mutational spectrum causing syndromic and non-syndromic retinal dystrophies in a large cohort of Mexican patients. Mol Vis 2023; 29:31-38. [PMID: 37287646 PMCID: PMC10243674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 04/28/2023] [Indexed: 06/09/2023] Open
Abstract
Background Mutations in the USH2A gene are the leading cause of both non-syndromic autosomal recessive retinitis pigmentosa (RP) and Usher syndrome, a syndromic form of RP characterized by retinal dystrophy and sensorineural hearing loss. To contribute to the expansion of the USH2A-related molecular spectrum, the results of genetic screening in a large cohort of Mexican patients are presented. Methods The study population comprised 61 patients with a clinical diagnosis of either non-syndromic RP (n = 30) or Usher syndrome type 2 (USH2; n = 31) who were demonstrated to carry biallelic pathogenic variants in USH2A in a three-year period. Genetic screening was performed either by gene panel sequencing or by exome sequencing. A total of 72 available first- or second-degree relatives were also genotyped for familial segregation of the identified variants. Results The USH2A mutational spectrum in RP patients included 39 distinct pathogenic variants, most of them of the missense type. The most common RP-causing variants were p.Cys759Phe (c.2276G>T), p.Glu767Serfs*21 (c.2299delG), and p.Cys319Tyr (c.956G>A), which together accounted for 25% of all RP variants. Novel USH2A mutations included three nonsense, two missense, two frameshift, and one intragenic deletion. The USH2A mutational spectrum in USH2 patients included 26 distinct pathogenic variants, most of them of the nonsense and frameshift types. The most common Usher syndrome-causing variants were p.Glu767Serfs*21 (c.2299delG), p.Arg334Trp (c.1000C>T), and c.12067-2A>G), which together accounted for 42% of all USH2-related variants. Novel Usher syndrome USH2A mutations included six nonsense, four frameshift, and two missense mutations. The c.2299delG mutation was associated with a common haplotype for SNPs located in exons 2-21 of USH2A, indicating a founder mutation effect. Conclusions Our work expands the USH2A mutational profile by identifying 20 novel pathogenic variants causing syndromic and non-syndromic retinal dystrophy. The prevalent c.2299delG allele is shown to arise from a founder effect. Our results emphasize the usefulness of molecular screening in underrepresented populations for a better characterization of the molecular spectrum of common monogenic diseases.
Collapse
Affiliation(s)
- Vianey Ordoñez-Labastida
- Rare Disease Diagnostic Unit, Faculty of Medicine, National Autonomous University of Mexico (UNAM), Mexico City, Mexico
- Department of Genetics, Institute of Ophthalmology “Conde de Valenciana,” Mexico City, Mexico
- Faculty of Medicine, Autonomous University of the State of Morelos (UAEM), Morelos, Mexico
| | - Oscar F. Chacon-Camacho
- Department of Genetics, Institute of Ophthalmology “Conde de Valenciana,” Mexico City, Mexico
- Carrera Médico Cirujano, Facultad de Estudios Superiores Iztacala, UNAM, Mexico City, Mexico
| | | | - Juan C. Zenteno
- Rare Disease Diagnostic Unit, Faculty of Medicine, National Autonomous University of Mexico (UNAM), Mexico City, Mexico
- Department of Genetics, Institute of Ophthalmology “Conde de Valenciana,” Mexico City, Mexico
- Department of Biochemistry, Faculty of Medicine, UNAM, Mexico City, Mexico
| |
Collapse
|
9
|
Zhang J, Guan J, Wang Q. [Genetics of pediatric hearing loss]. LIN CHUANG ER BI YAN HOU TOU JING WAI KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY, HEAD, AND NECK SURGERY 2023; 37:181-185. [PMID: 36843515 PMCID: PMC10320671 DOI: 10.13201/j.issn.2096-7993.2023.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Indexed: 02/28/2023]
Abstract
With the rapid development of sequencing technology and bioinformatics, the genetic research and related clinical practice of pediatric hearing loss have also made significant progress. This review summarized and analyzed the genetic causes of hearing impairment in children and the research progress of related genetic diagnosis and screening, in order to provide reference for the prevention and treatment of pediatric hearing loss and related research.
Collapse
Affiliation(s)
- Jiao Zhang
- Department of Audiology and Vestibular Medicine,Institute of Otolaryngology,Senior Department of Otolaryngology Head and Neck Surgery,the Sixth Medical Center of Chinese PLA General Hospital,National Clinical Research Center for Otolaryngologic Diseases,Beijing,100048,China
| | - Jing Guan
- Department of Otolaryngology Head and Neck Surgery,the First Medical Center of Chinese PLA General Hospital
| | - Qiuju Wang
- Department of Audiology and Vestibular Medicine,Institute of Otolaryngology,Senior Department of Otolaryngology Head and Neck Surgery,the Sixth Medical Center of Chinese PLA General Hospital,National Clinical Research Center for Otolaryngologic Diseases,Beijing,100048,China
| |
Collapse
|
10
|
Towards a Cure for HARS Disease. Genes (Basel) 2023; 14:genes14020254. [PMID: 36833180 PMCID: PMC9956352 DOI: 10.3390/genes14020254] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/11/2023] [Accepted: 01/13/2023] [Indexed: 01/20/2023] Open
Abstract
Histidyl-tRNA synthetase (HARS) ligates histidine to its cognate transfer RNA (tRNAHis). Mutations in HARS cause the human genetic disorders Usher syndrome type 3B (USH3B) and Charcot-Marie-Tooth syndrome type 2W (CMT2W). Treatment for these diseases remains symptomatic, and no disease specific treatments are currently available. Mutations in HARS can lead to destabilization of the enzyme, reduced aminoacylation, and decreased histidine incorporation into the proteome. Other mutations lead to a toxic gain-of-function and mistranslation of non-cognate amino acids in response to histidine codons, which can be rescued by histidine supplementation in vitro. We discuss recent advances in characterizing HARS mutations and potential applications of amino acid and tRNA therapy for future gene and allele specific therapy.
Collapse
|
11
|
Kim KS, Koo HY, Bok J. Alternative splicing in shaping the molecular landscape of the cochlea. Front Cell Dev Biol 2023; 11:1143428. [PMID: 36936679 PMCID: PMC10018040 DOI: 10.3389/fcell.2023.1143428] [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: 01/13/2023] [Accepted: 02/16/2023] [Indexed: 03/06/2023] Open
Abstract
The cochlea is a complex organ comprising diverse cell types with highly specialized morphology and function. Until now, the molecular underpinnings of its specializations have mostly been studied from a transcriptional perspective, but accumulating evidence points to post-transcriptional regulation as a major source of molecular diversity. Alternative splicing is one of the most prevalent and well-characterized post-transcriptional regulatory mechanisms. Many molecules important for hearing, such as cadherin 23 or harmonin, undergo alternative splicing to produce functionally distinct isoforms. Some isoforms are expressed specifically in the cochlea, while some show differential expression across the various cochlear cell types and anatomical regions. Clinical phenotypes that arise from mutations affecting specific splice variants testify to the functional relevance of these isoforms. All these clues point to an essential role for alternative splicing in shaping the unique molecular landscape of the cochlea. Although the regulatory mechanisms controlling alternative splicing in the cochlea are poorly characterized, there are animal models with defective splicing regulators that demonstrate the importance of RNA-binding proteins in maintaining cochlear function and cell survival. Recent technological breakthroughs offer exciting prospects for overcoming some of the long-standing hurdles that have complicated the analysis of alternative splicing in the cochlea. Efforts toward this end will help clarify how the remarkable diversity of the cochlear transcriptome is both established and maintained.
Collapse
Affiliation(s)
- Kwan Soo Kim
- Department of Anatomy, Yonsei University College of Medicine, Seoul, Republic of Korea
- Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Hei Yeun Koo
- Department of Anatomy, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jinwoong Bok
- Department of Anatomy, Yonsei University College of Medicine, Seoul, Republic of Korea
- Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, Republic of Korea
- *Correspondence: Jinwoong Bok,
| |
Collapse
|
12
|
Induced Pluripotent Stem Cells, a Stepping Stone to In Vitro Human Models of Hearing Loss. Cells 2022; 11:cells11203331. [PMID: 36291196 PMCID: PMC9600035 DOI: 10.3390/cells11203331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 10/05/2022] [Accepted: 10/14/2022] [Indexed: 11/28/2022] Open
Abstract
Hearing loss is the most prevalent sensorineural impairment in humans. Yet despite very active research, no effective therapy other than the cochlear implant has reached the clinic. Main reasons for this failure are the multifactorial nature of the disorder, its heterogeneity, and a late onset that hinders the identification of etiological factors. Another problem is the lack of human samples such that practically all the work has been conducted on animals. Although highly valuable data have been obtained from such models, there is the risk that inter-species differences exist that may compromise the relevance of the gathered data. Human-based models are therefore direly needed. The irruption of human induced pluripotent stem cell technologies in the field of hearing research offers the possibility to generate an array of otic cell models of human origin; these may enable the identification of guiding signalling cues during inner ear development and of the mechanisms that lead from genetic alterations to pathology. These models will also be extremely valuable when conducting ototoxicity analyses and when exploring new avenues towards regeneration in the inner ear. This review summarises some of the work that has already been conducted with these cells and contemplates future possibilities.
Collapse
|
13
|
Leong YC, Di Foggia V, Pramod H, Bitner-Glindzicz M, Patel A, Sowden JC. Molecular pathology of Usher 1B patient-derived retinal organoids at single cell resolution. Stem Cell Reports 2022; 17:2421-2437. [DOI: 10.1016/j.stemcr.2022.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 11/08/2022] Open
|
14
|
Elander J, Ullmark T, Ehrencrona H, Jonson T, Piccinelli P, Samuelsson S, Löwgren K, Falkenius-Schmidt K, Ehinger J, Stenfeldt K, Värendh M. Extended genetic diagnostics for children with profound sensorineural hearing loss by implementing massive parallel sequencing. Diagnostic outcome, family experience and clinical implementation. Int J Pediatr Otorhinolaryngol 2022; 159:111218. [PMID: 35779349 DOI: 10.1016/j.ijporl.2022.111218] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 06/12/2022] [Accepted: 06/22/2022] [Indexed: 10/17/2022]
Abstract
OBJECTIVES The aim of this study was to investigate genetic outcomes, analyze the family experience, and describe the process of implementing genetic sequencing for children with profound sensorineural hearing loss (SNHL) at a tertial audiological center in southern Sweden. DESIGN This is a prospective pilot study including eleven children with profound bilateral SNHL who underwent cochlear implant surgery. Genetic diagnostic investigation was performed with whole exome sequencing (WES) complemented with XON-array to identify copy number variants, using a manually curated gene panel incorporating 179 genes associated with non-syndromic and syndromic SNHL. Mitochondrial DNA (mtDNA) from blood was examined separately. A patient reported experience measures (PREM) questionnaire was used to evaluate parental experience. We also describe here the process of implementing WES in an audiology department. RESULTS Six female and five male children (mean 3.4 years, SD 3.5 years), with profound bilateral SNHL were included. Genetic variants of interest were found in six subjects (55%), where three (27%) could be classified as pathogenic or likely pathogenic. Among the six cases, one child was found to have a homozygous pathogenic variant in MYO7A and two children had homozygous likely pathogenic variants in SLC26A4 and PCDH15, respectively. One was carrying a compound heterozygote frameshift variant of uncertain significance (VUS) on one allele and in trans, a likely pathogenic deletion on the other allele in PCDH15. Two subjects had homozygous VUS in PCDH15 and ADGRV1, respectively. In five of the cases the variants were in genes associated with Usher syndrome. For one of the likely pathogenic variants, the finding was related to Pendred syndrome. No mtDNA variants related to SNHL were found. The PREM questionnaire revealed that the families had difficulty in fully understanding the results of the genetic analysis. However, the parents of all eleven (100%) subjects still recommended that other families with children with SNHL should undergo genetic testing. Specifically addressed referrals for prompt complementary clinical examination and more individualized care were possible, based on the genetic results. Close clinical collaboration between different specialists, including physicians of audiology, audiologists, clinical geneticists, ophthalmologists, pediatricians, otoneurologists, physiotherapists and hearing habilitation teams was initiated during the implementation of the new regime. For all professionals involved, a better knowledge of the diversity of the genetic background of hearing loss was achieved. CONCLUSIONS Whole exome sequencing and XON-array using a panel of genes associated with SNHL had a high diagnostic yield, added value to the families, and provided guidance for further examinations and habilitation for the child. Great care should be taken to thoroughly inform parents about the genetic test result. Collaborations between departments were intensified and knowledge of hearing genomics was increased among the staff.
Collapse
Affiliation(s)
- Johanna Elander
- Lund University, Skåne University Hospital, Department of Clinical Sciences Lund, Otorhinolaryngology, Head and Neck Surgery, 221 84, Lund, Sweden.
| | - Tove Ullmark
- Department of Clinical Genetics and Pathology, Office for Medical Services, Region Skåne, 221 85, Lund, Sweden
| | - Hans Ehrencrona
- Department of Clinical Genetics and Pathology, Office for Medical Services, Region Skåne, 221 85, Lund, Sweden; Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, 221 85, Lund, Sweden
| | - Tord Jonson
- Department of Clinical Genetics and Pathology, Office for Medical Services, Region Skåne, 221 85, Lund, Sweden
| | - Paul Piccinelli
- Department of Clinical Genetics and Pathology, Office for Medical Services, Region Skåne, 221 85, Lund, Sweden
| | - Sofie Samuelsson
- Department of Clinical Genetics and Pathology, Office for Medical Services, Region Skåne, 221 85, Lund, Sweden
| | - Karolina Löwgren
- Lund University, Skåne University Hospital, Department of Clinical Sciences Lund, Otorhinolaryngology, Head and Neck Surgery, 221 84, Lund, Sweden
| | - Karolina Falkenius-Schmidt
- Lund University, Skåne University Hospital, Department of Clinical Sciences Lund, Otorhinolaryngology, Head and Neck Surgery, 221 84, Lund, Sweden
| | - Johannes Ehinger
- Lund University, Skåne University Hospital, Department of Clinical Sciences Lund, Otorhinolaryngology, Head and Neck Surgery, 221 84, Lund, Sweden
| | - Karin Stenfeldt
- Lund University, Skåne University Hospital, Department of Clinical Sciences Lund, Otorhinolaryngology, Head and Neck Surgery, 221 84, Lund, Sweden; Lund University, Department of Clinical Sciences Lund, Logopedics, Phoniatrics and Audiology, 221 84, Lund, Sweden
| | - Maria Värendh
- Lund University, Skåne University Hospital, Department of Clinical Sciences Lund, Otorhinolaryngology, Head and Neck Surgery, 221 84, Lund, Sweden
| |
Collapse
|
15
|
Meunier A, Zanlonghi X, Roux AF, Fils JF, Caspers L, Migeotte I, Abramowicz M, Meunier I. Natural history of Usher type 2 with the c.2299delG mutation of USH2A in a large cohort. Ophthalmic Genet 2022; 43:470-475. [PMID: 35345973 DOI: 10.1080/13816810.2022.2051191] [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: 10/18/2022]
Abstract
BACKGROUND The c.2299delG mutation is prevalent and accounts for 24.5% USH2A pathogenic variants, with promising prospects for customized gene therapy. MATERIALS AND METHODS We compared the ocular and auditory phenotypes in a retrospective cohort of 169 Usher type 2 patients, with and without the c.2299delG allele, including visual acuity, slit-lamp examination, optical coherence tomography, kinetic perimetry, and audiometric assessment to define the hearing disability. Statistical methods used were covariate balancing propensity score and adjusted survival curves log-rank test for the analysis of visual acuity. RESULTS We compare 54 Usher patients (31%) carrying at least one c.2299delG allele to 109 patients without this variant. The mean ages at onset of night blindness (14 years) and onset of peripheral vision deficiency (24 years) were similar in both groups, as was the severity of hearing loss (p = 0.731), even in homozygotes (p = 0.136). Based on the covariate balancing propensity score, the c.2299delG carrier patients developed cataract and reached a BCVA of 20/63 earlier than patients without this mutation (mean age 36 versus 42 y.o.; and 52.2 versus 55.1 y.o., respectively). Using adjusted survival curves and a log-rank test based on inverse probability weighting, patients with the c.2299delG variant reach blindness (BCVA <20/400) at 42.3 years old instead of 79.8 years for other USH2A pathogenic variants. CONCLUSIONS We conclude that c.2299delG is associated with a more severe phenotype of the Usher type 2, in homozygotes and in compound heterozygotes.
Collapse
Affiliation(s)
- Audrey Meunier
- Department of Ophthalmology, University Hospital Saint-Pierre, Université Libre de Bruxelles (ULB), Bruxelles, Belgium
| | - Xavier Zanlonghi
- Centre de compétence Maladies rares, Jules Verne Clinic, Nantes, France
| | - Anne-Françoise Roux
- Laboratory of Molecular Genetics, University of Montpellier, Montpellier University Hospital, Montpellier, France.,Institute for Neurosciences of Montpellier, INSERM, University of Montpellier, Montpellier, France
| | | | - Laure Caspers
- Department of Ophthalmology, University Hospital Saint-Pierre, Université Libre de Bruxelles (ULB), Bruxelles, Belgium
| | - Isabelle Migeotte
- Genetic department, IRIBHM, Université Libre de Bruxelles, Bruxelles, Belgium
| | - Marc Abramowicz
- Genetic department, IRIBHM, Université Libre de Bruxelles, Bruxelles, Belgium.,Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Isabelle Meunier
- Institute for Neurosciences of Montpellier, INSERM, University of Montpellier, Montpellier, France.,National center in rare diseases Maolya, Genetics of Sensory Diseases, University Hospital, Sensgene Care Network, Montpellier, France
| |
Collapse
|
16
|
Holzinger D, Hofer J, Dall M, Fellinger J. Multidimensional Family-Centred Early Intervention in Children with Hearing Loss: A Conceptual Model. J Clin Med 2022; 11:jcm11061548. [PMID: 35329873 PMCID: PMC8949393 DOI: 10.3390/jcm11061548] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/07/2022] [Accepted: 03/09/2022] [Indexed: 02/04/2023] Open
Abstract
At least two per thousand newborns are affected by hearing loss, with up to 40% with an additional disability. Early identification by universal newborn hearing screening and early intervention services are available in many countries around the world, with limited data on their effectiveness and a lack of knowledge about specific intervention-related determinants of child and family outcomes. This concept paper aimed to better understand the mechanisms by which multi-dimensional family-centred early intervention influences child outcomes, through parent behaviour, targeted by intervention by a review of the literature, primarily in the field of childhood hearing loss, supplemented by research findings on physiological and atypical child development. We present a conceptual model of influences of multi-disciplinary family-centred early intervention on family coping/functioning and parent–child interaction, with effects on child psycho-social and cognitive outcomes. Social communication and language skills are postulated as mediators between parent–child interaction and non-verbal child outcomes. Multi-disciplinary networks of professionals trained in family-centred practice and the evaluation of existing services, with respect to best practice guidelines for family-centred early intervention, are recommended. There is a need for longitudinal epidemiological studies, including specific intervention measures, family behaviours and multidimensional child outcomes.
Collapse
Affiliation(s)
- Daniel Holzinger
- Research Institute for Developmental Medicine, Johannes Kepler University Linz, 4020 Linz, Austria; (J.H.); (M.D.); (J.F.)
- Institute of Neurology of Senses and Language, Hospital of St. John of God, 4020 Linz, Austria
- Institute of Linguistics, University of Graz, 8010 Graz, Austria
- Correspondence: or
| | - Johannes Hofer
- Research Institute for Developmental Medicine, Johannes Kepler University Linz, 4020 Linz, Austria; (J.H.); (M.D.); (J.F.)
- Institute of Neurology of Senses and Language, Hospital of St. John of God, 4020 Linz, Austria
- Department of Paediatrics I, Innsbruck Medical University, 6020 Innsbruck, Austria
| | - Magdalena Dall
- Research Institute for Developmental Medicine, Johannes Kepler University Linz, 4020 Linz, Austria; (J.H.); (M.D.); (J.F.)
| | - Johannes Fellinger
- Research Institute for Developmental Medicine, Johannes Kepler University Linz, 4020 Linz, Austria; (J.H.); (M.D.); (J.F.)
- Institute of Neurology of Senses and Language, Hospital of St. John of God, 4020 Linz, Austria
- Division of Social Psychiatry, University Clinic for Psychiatry and Psychotherapy, Medical University of Vienna, 1090 Vienna, Austria
| |
Collapse
|
17
|
Al-Choboq J, Ferlazzo ML, Sonzogni L, Granzotto A, El-Nachef L, Maalouf M, Berthel E, Foray N. Usher Syndrome Belongs to the Genetic Diseases Associated with Radiosensitivity: Influence of the ATM Protein Kinase. Int J Mol Sci 2022; 23:ijms23031570. [PMID: 35163494 PMCID: PMC8836140 DOI: 10.3390/ijms23031570] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 01/23/2022] [Accepted: 01/27/2022] [Indexed: 12/23/2022] Open
Abstract
Usher syndrome (USH) is a rare autosomal recessive disease characterized by the combination of hearing loss, visual impairment due to retinitis pigmentosa, and in some cases vestibular dysfunctions. Studies published in the 1980s reported that USH is associated with cellular radiosensitivity. However, the molecular basis of this particular phenotype has not yet been documented. The aim of this study was therefore to document the radiosensitivity of USH1—a subset of USH—by examining the radiation-induced nucleo-shuttling of ATM (RIANS), as well as the functionality of the repair and signaling pathways of the DNA double-strand breaks (DSBs) in three skin fibroblasts derived from USH1 patients. The clonogenic cell survival, the micronuclei, the nuclear foci formed by the phosphorylated forms of the X variant of the H2A histone (ɣH2AX), the phosphorylated forms of the ATM protein (pATM), and the meiotic recombination 11 nuclease (MRE11) were used as cellular and molecular endpoints. The interaction between the ATM and USH1 proteins was also examined by proximity ligation assay. The results showed that USH1 fibroblasts were associated with moderate but significant radiosensitivity, high yield of micronuclei, and impaired DSB recognition but normal DSB repair, likely caused by a delayed RIANS, suggesting a possible sequestration of ATM by some USH1 proteins overexpressed in the cytoplasm. To our knowledge, this report is the first radiobiological characterization of cells from USH1 patients at both molecular and cellular scales.
Collapse
Affiliation(s)
- Joëlle Al-Choboq
- Inserm, U1296 Unit, Radiation: Defense, Health and Environment, Centre Léon-Bérard, 28 rue Laennec, 69008 Lyon, France; (J.A.-C.); (M.L.F.); (L.S.); (A.G.); (L.E.-N.); (E.B.)
| | - Mélanie L. Ferlazzo
- Inserm, U1296 Unit, Radiation: Defense, Health and Environment, Centre Léon-Bérard, 28 rue Laennec, 69008 Lyon, France; (J.A.-C.); (M.L.F.); (L.S.); (A.G.); (L.E.-N.); (E.B.)
| | - Laurène Sonzogni
- Inserm, U1296 Unit, Radiation: Defense, Health and Environment, Centre Léon-Bérard, 28 rue Laennec, 69008 Lyon, France; (J.A.-C.); (M.L.F.); (L.S.); (A.G.); (L.E.-N.); (E.B.)
| | - Adeline Granzotto
- Inserm, U1296 Unit, Radiation: Defense, Health and Environment, Centre Léon-Bérard, 28 rue Laennec, 69008 Lyon, France; (J.A.-C.); (M.L.F.); (L.S.); (A.G.); (L.E.-N.); (E.B.)
| | - Laura El-Nachef
- Inserm, U1296 Unit, Radiation: Defense, Health and Environment, Centre Léon-Bérard, 28 rue Laennec, 69008 Lyon, France; (J.A.-C.); (M.L.F.); (L.S.); (A.G.); (L.E.-N.); (E.B.)
| | - Mira Maalouf
- Department of Chemistry and Biochemistry, Faculty of Sciences II, Lebanese University, Fanar 1202, Lebanon;
| | - Elise Berthel
- Inserm, U1296 Unit, Radiation: Defense, Health and Environment, Centre Léon-Bérard, 28 rue Laennec, 69008 Lyon, France; (J.A.-C.); (M.L.F.); (L.S.); (A.G.); (L.E.-N.); (E.B.)
| | - Nicolas Foray
- Inserm, U1296 Unit, Radiation: Defense, Health and Environment, Centre Léon-Bérard, 28 rue Laennec, 69008 Lyon, France; (J.A.-C.); (M.L.F.); (L.S.); (A.G.); (L.E.-N.); (E.B.)
- Correspondence: ; Tel.: +33-4-78-78-28-28
| |
Collapse
|
18
|
Yusuf IH, Garrett A, MacLaren RE, Issa PC. Retinal cadherins and the retinal cadherinopathies: Current concepts and future directions. Prog Retin Eye Res 2022; 90:101038. [DOI: 10.1016/j.preteyeres.2021.101038] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 12/13/2021] [Accepted: 12/20/2021] [Indexed: 12/18/2022]
|
19
|
Molday RS, Garces FA, Scortecci JF, Molday LL. Structure and function of ABCA4 and its role in the visual cycle and Stargardt macular degeneration. Prog Retin Eye Res 2021; 89:101036. [PMID: 34954332 DOI: 10.1016/j.preteyeres.2021.101036] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/07/2021] [Accepted: 12/13/2021] [Indexed: 12/17/2022]
Abstract
ABCA4 is a member of the superfamily of ATP-binding cassette (ABC) transporters that is preferentially localized along the rim region of rod and cone photoreceptor outer segment disc membranes. It uses the energy from ATP binding and hydrolysis to transport N-retinylidene-phosphatidylethanolamine (N-Ret-PE), the Schiff base adduct of retinal and phosphatidylethanolamine, from the lumen to the cytoplasmic leaflet of disc membranes. This ensures that all-trans-retinal and excess 11-cis-retinal are efficiently cleared from photoreceptor cells thereby preventing the accumulation of toxic retinoid compounds. Loss-of-function mutations in the gene encoding ABCA4 cause autosomal recessive Stargardt macular degeneration, also known as Stargardt disease (STGD1), and related autosomal recessive retinopathies characterized by impaired central vision and an accumulation of lipofuscin and bis-retinoid compounds. High resolution structures of ABCA4 in its substrate and nucleotide free state and containing bound N-Ret-PE or ATP have been determined by cryo-electron microscopy providing insight into the molecular architecture of ABCA4 and mechanisms underlying substrate recognition and conformational changes induced by ATP binding. The expression and functional characterization of a large number of disease-causing missense ABCA4 variants have been determined. These studies have shed light into the molecular mechanisms underlying Stargardt disease and a classification that reliably predicts the effect of a specific missense mutation on the severity of the disease. They also provide a framework for developing rational therapeutic treatments for ABCA4-associated diseases.
Collapse
Affiliation(s)
- Robert S Molday
- Department of Biochemistry & Molecular Biology, University of British Columbia, Vancouver, B.C., Canada; Department of Ophthalmology & Visual Sciences, University of British Columbia, Vancouver, B.C., Canada.
| | - Fabian A Garces
- Department of Biochemistry & Molecular Biology, University of British Columbia, Vancouver, B.C., Canada
| | | | - Laurie L Molday
- Department of Biochemistry & Molecular Biology, University of British Columbia, Vancouver, B.C., Canada
| |
Collapse
|
20
|
Houston BJ, Riera-Escamilla A, Wyrwoll MJ, Salas-Huetos A, Xavier MJ, Nagirnaja L, Friedrich C, Conrad DF, Aston KI, Krausz C, Tüttelmann F, O’Bryan MK, Veltman JA, Oud MS. A systematic review of the validated monogenic causes of human male infertility: 2020 update and a discussion of emerging gene-disease relationships. Hum Reprod Update 2021; 28:15-29. [PMID: 34498060 PMCID: PMC8730311 DOI: 10.1093/humupd/dmab030] [Citation(s) in RCA: 94] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 08/05/2021] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Human male infertility has a notable genetic component, including well-established diagnoses such as Klinefelter syndrome, Y-chromosome microdeletions and monogenic causes. Approximately 4% of all infertile men are now diagnosed with a genetic cause, but a majority (60-70%) remain without a clear diagnosis and are classified as unexplained. This is likely in large part due to a delay in the field adopting next-generation sequencing (NGS) technologies, and the absence of clear statements from field leaders as to what constitutes a validated cause of human male infertility (the current paper aims to address this). Fortunately, there has been a significant increase in the number of male infertility NGS studies. These have revealed a considerable number of novel gene-disease relationships (GDRs), which each require stringent assessment to validate the strength of genotype-phenotype associations. To definitively assess which of these GDRs are clinically relevant, the International Male Infertility Genomics Consortium (IMIGC) has identified the need for a systematic review and a comprehensive overview of known male infertility genes and an assessment of the evidence for reported GDRs. OBJECTIVE AND RATIONALE In 2019, the first standardised clinical validity assessment of monogenic causes of male infertility was published. Here, we provide a comprehensive update of the subsequent 1.5 years, employing the joint expertise of the IMIGC to systematically evaluate all available evidence (as of 1 July 2020) for monogenic causes of isolated or syndromic male infertility, endocrine disorders or reproductive system abnormalities affecting the male sex organs. In addition, we systematically assessed the evidence for all previously reported possible monogenic causes of male infertility, using a framework designed for a more appropriate clinical interpretation of disease genes. SEARCH METHODS We performed a literature search according to the PRISMA guidelines up until 1 July 2020 for publications in English, using search terms related to 'male infertility' in combination with the word 'genetics' in PubMed. Next, the quality and the extent of all evidence supporting selected genes were assessed using an established and standardised scoring method. We assessed the experimental quality, patient phenotype assessment and functional evidence based on gene expression, mutant in-vitro cell and in-vivo animal model phenotypes. A final score was used to determine the clinical validity of each GDR, across the following five categories: no evidence, limited, moderate, strong or definitive. Variants were also reclassified according to the American College of Medical Genetics and Genomics-Association for Molecular Pathology (ACMG-AMP) guidelines and were recorded in spreadsheets for each GDR, which are available at imigc.org. OUTCOMES The primary outcome of this review was an overview of all known GDRs for monogenic causes of human male infertility and their clinical validity. We identified a total of 120 genes that were moderately, strongly or definitively linked to 104 infertility phenotypes. WIDER IMPLICATIONS Our systematic review curates all currently available evidence to reveal the strength of GDRs in male infertility. The existing guidelines for genetic testing in male infertility cases are based on studies published 25 years ago, and an update is far overdue. The identification of 104 high-probability 'human male infertility genes' is a 33% increase from the number identified in 2019. The insights generated in the current review will provide the impetus for an update of existing guidelines, will inform novel evidence-based genetic testing strategies used in clinics, and will identify gaps in our knowledge of male infertility genetics. We discuss the relevant international guidelines regarding research related to gene discovery and provide specific recommendations to the field of male infertility. Based on our findings, the IMIGC consortium recommend several updates to the genetic testing standards currently employed in the field of human male infertility, most important being the adoption of exome sequencing, or at least sequencing of the genes validated in this study, and expanding the patient groups for which genetic testing is recommended.
Collapse
Affiliation(s)
- Brendan J Houston
- School of BioSciences and Bio21 Institute, The University of Melbourne, Parkville, VIC, Australia
| | - Antoni Riera-Escamilla
- Andrology Department, Fundació Puigvert, Universitat Autònoma de Barcelona, Instituto de Investigaciones Biomédicas Sant Pau (IIB-Sant Pau), Barcelona, Catalonia, Spain
| | - Margot J Wyrwoll
- Institute of Reproductive Genetics, University of Münster, Münster, Germany
| | - Albert Salas-Huetos
- Andrology and IVF Laboratory, Division of Urology, Department of Surgery, University of Utah School of Medicine, Salt Lake City, UT, USA
- Department of Nutrition, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, USA
| | - Miguel J Xavier
- Faculty of Medical Sciences, Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Liina Nagirnaja
- Division of Genetics, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
- Genetics of Male Infertility Initiative (GEMINI)
| | - Corinna Friedrich
- Institute of Reproductive Genetics, University of Münster, Münster, Germany
| | - Don F Conrad
- Division of Genetics, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
- Genetics of Male Infertility Initiative (GEMINI)
- International Male Infertility Genomics Consortium (IMIGC)
| | - Kenneth I Aston
- Andrology and IVF Laboratory, Division of Urology, Department of Surgery, University of Utah School of Medicine, Salt Lake City, UT, USA
- Genetics of Male Infertility Initiative (GEMINI)
- International Male Infertility Genomics Consortium (IMIGC)
| | - Csilla Krausz
- Genetics of Male Infertility Initiative (GEMINI)
- International Male Infertility Genomics Consortium (IMIGC)
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio”, Centre of Excellence DeNothe, University of Florence, Florence, Italy
| | - Frank Tüttelmann
- Institute of Reproductive Genetics, University of Münster, Münster, Germany
- International Male Infertility Genomics Consortium (IMIGC)
| | - Moira K O’Bryan
- School of BioSciences and Bio21 Institute, The University of Melbourne, Parkville, VIC, Australia
- Genetics of Male Infertility Initiative (GEMINI)
- International Male Infertility Genomics Consortium (IMIGC)
| | - Joris A Veltman
- Faculty of Medical Sciences, Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
- International Male Infertility Genomics Consortium (IMIGC)
| | - Manon S Oud
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboudumc, Nijmegen, the Netherlands
| |
Collapse
|
21
|
Łysyganicz PK, Pooranachandran N, Liu X, Adamson KI, Zielonka K, Elworthy S, van Eeden FJ, Grierson AJ, Malicki JJ. Loss of Deacetylation Enzymes Hdac6 and Sirt2 Promotes Acetylation of Cytoplasmic Tubulin, but Suppresses Axonemal Acetylation in Zebrafish Cilia. Front Cell Dev Biol 2021; 9:676214. [PMID: 34268305 PMCID: PMC8276265 DOI: 10.3389/fcell.2021.676214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 05/13/2021] [Indexed: 01/26/2023] Open
Abstract
Cilia are evolutionarily highly conserved organelles with important functions in many organs. The extracellular component of the cilium protruding from the plasma membrane comprises an axoneme composed of microtubule doublets, arranged in a 9 + 0 conformation in primary cilia or 9 + 2 in motile cilia. These microtubules facilitate transport of intraflagellar cargoes along the axoneme. They also provide structural stability to the cilium, which may play an important role in sensory cilia, where signals are received from the movement of extracellular fluid. Post-translational modification of microtubules in cilia is a well-studied phenomenon, and acetylation on lysine 40 (K40) of alpha tubulin is prominent in cilia. It is believed that this modification contributes to the stabilization of cilia. Two classes of enzymes, histone acetyltransferases and histone deacetylases, mediate regulation of tubulin acetylation. Here we use a genetic approach, immunocytochemistry and behavioral tests to investigate the function of tubulin deacetylases in cilia in a zebrafish model. By mutating three histone deacetylase genes (Sirt2, Hdac6, and Hdac10), we identify an unforeseen role for Hdac6 and Sirt2 in cilia. As expected, mutation of these genes leads to increased acetylation of cytoplasmic tubulin, however, surprisingly it caused decreased tubulin acetylation in cilia in the developing eye, ear, brain and kidney. Cilia in the ear and eye showed elevated levels of mono-glycylated tubulin suggesting a compensatory mechanism. These changes did not affect the length or morphology of cilia, however, functional defects in balance was observed, suggesting that the level of tubulin acetylation may affect function of the cilium.
Collapse
Affiliation(s)
- Paweł K Łysyganicz
- The Bateson Centre, The University of Sheffield, Sheffield, United Kingdom.,Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| | | | - Xinming Liu
- The School of Clinical Dentistry, The University of Sheffield, Sheffield, United Kingdom
| | - Kathryn I Adamson
- The Bateson Centre, The University of Sheffield, Sheffield, United Kingdom.,Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Katarzyna Zielonka
- The Bateson Centre, The University of Sheffield, Sheffield, United Kingdom.,Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| | - Stone Elworthy
- The Bateson Centre, The University of Sheffield, Sheffield, United Kingdom.,Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| | - Fredericus J van Eeden
- The Bateson Centre, The University of Sheffield, Sheffield, United Kingdom.,Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| | - Andrew J Grierson
- The Bateson Centre, The University of Sheffield, Sheffield, United Kingdom.,Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Jarema J Malicki
- The Bateson Centre, The University of Sheffield, Sheffield, United Kingdom.,Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| |
Collapse
|
22
|
Sánchez-Bellver L, Toulis V, Marfany G. On the Wrong Track: Alterations of Ciliary Transport in Inherited Retinal Dystrophies. Front Cell Dev Biol 2021; 9:623734. [PMID: 33748110 PMCID: PMC7973215 DOI: 10.3389/fcell.2021.623734] [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: 10/30/2020] [Accepted: 02/09/2021] [Indexed: 01/14/2023] Open
Abstract
Ciliopathies are a group of heterogeneous inherited disorders associated with dysfunction of the cilium, a ubiquitous microtubule-based organelle involved in a broad range of cellular functions. Most ciliopathies are syndromic, since several organs whose cells produce a cilium, such as the retina, cochlea or kidney, are affected by mutations in ciliary-related genes. In the retina, photoreceptor cells present a highly specialized neurosensory cilium, the outer segment, stacked with membranous disks where photoreception and phototransduction occurs. The daily renewal of the more distal disks is a unique characteristic of photoreceptor outer segments, resulting in an elevated protein demand. All components necessary for outer segment formation, maintenance and function have to be transported from the photoreceptor inner segment, where synthesis occurs, to the cilium. Therefore, efficient transport of selected proteins is critical for photoreceptor ciliogenesis and function, and any alteration in either cargo delivery to the cilium or intraciliary trafficking compromises photoreceptor survival and leads to retinal degeneration. To date, mutations in more than 100 ciliary genes have been associated with retinal dystrophies, accounting for almost 25% of these inherited rare diseases. Interestingly, not all mutations in ciliary genes that cause retinal degeneration are also involved in pleiotropic pathologies in other ciliated organs. Depending on the mutation, the same gene can cause syndromic or non-syndromic retinopathies, thus emphasizing the highly refined specialization of the photoreceptor neurosensory cilia, and raising the possibility of photoreceptor-specific molecular mechanisms underlying common ciliary functions such as ciliary transport. In this review, we will focus on ciliary transport in photoreceptor cells and discuss the molecular complexity underpinning retinal ciliopathies, with a special emphasis on ciliary genes that, when mutated, cause either syndromic or non-syndromic retinal ciliopathies.
Collapse
Affiliation(s)
- Laura Sánchez-Bellver
- Departament de Genètica, Microbiologia i Estadística, Universitat de Barcelona, Barcelona, Spain
- Institute of Biomedicine (IBUB-IRSJD), Universitat de Barcelona, Barcelona, Spain
| | - Vasileios Toulis
- Departament de Genètica, Microbiologia i Estadística, Universitat de Barcelona, Barcelona, Spain
- CIBERER, ISCIII, Universitat de Barcelona, Barcelona, Spain
| | - Gemma Marfany
- Departament de Genètica, Microbiologia i Estadística, Universitat de Barcelona, Barcelona, Spain
- Institute of Biomedicine (IBUB-IRSJD), Universitat de Barcelona, Barcelona, Spain
- CIBERER, ISCIII, Universitat de Barcelona, Barcelona, Spain
| |
Collapse
|