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Domínguez-Ruiz M, Ruiz-Palmero L, Buonfiglio PI, García-Vaquero I, Gómez-Rosas E, Goñi M, Villamar M, Morín M, Moreno-Pelayo MA, Elgoyhen AB, del Castillo FJ, Dalamón V, del Castillo I. Novel Pathogenic Variants in the Gene Encoding Stereocilin ( STRC) Causing Non-Syndromic Moderate Hearing Loss in Spanish and Argentinean Subjects. Biomedicines 2023; 11:2943. [PMID: 38001944 PMCID: PMC10668944 DOI: 10.3390/biomedicines11112943] [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: 10/10/2023] [Revised: 10/24/2023] [Accepted: 10/27/2023] [Indexed: 11/26/2023] Open
Abstract
Non-syndromic hearing impairment (NSHI) is a very heterogeneous genetic condition, involving over 130 genes. Mutations in GJB2, encoding connexin-26, are a major cause of NSHI (the DFNB1 type), but few other genes have significant epidemiological contributions. Mutations in the STRC gene result in the DFNB16 type of autosomal recessive NSHI, a common cause of moderate hearing loss. STRC is located in a tandem duplicated region that includes the STRCP1 pseudogene, and so it is prone to rearrangements causing structural variations. Firstly, we screened a cohort of 122 Spanish familial cases of non-DFNB1 NSHI with at least two affected siblings and unaffected parents, and with different degrees of hearing loss (mild to profound). Secondly, we screened a cohort of 64 Spanish sporadic non-DFNB1 cases, and a cohort of 35 Argentinean non-DFNB1 cases, all of them with moderate hearing loss. Amplification of marker D15S784, massively parallel DNA sequencing, multiplex ligation-dependent probe amplification and long-range gene-specific PCR followed by Sanger sequencing were used to search and confirm single-nucleotide variants (SNVs) and deletions involving STRC. Causative variants were found in 13 Spanish familial cases (10.7%), 5 Spanish simplex cases (7.8%) and 2 Argentinean cases (5.7%). In all, 34 deleted alleles and 6 SNVs, 5 of which are novel. All affected subjects had moderate hearing impairment. Our results further support this strong genotype-phenotype correlation and highlight the significant contribution of STRC mutations to moderate NSHI in the Spanish population.
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Affiliation(s)
- María Domínguez-Ruiz
- Servicio de Genética, Hospital Universitario Ramón y Cajal, 28034 Madrid, Spain; (M.D.-R.); (L.R.-P.); (I.G.-V.); (E.G.-R.); (M.G.); (M.V.); (M.M.); (M.A.M.-P.); (F.J.d.C.)
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 28034 Madrid, Spain
| | - Laura Ruiz-Palmero
- Servicio de Genética, Hospital Universitario Ramón y Cajal, 28034 Madrid, Spain; (M.D.-R.); (L.R.-P.); (I.G.-V.); (E.G.-R.); (M.G.); (M.V.); (M.M.); (M.A.M.-P.); (F.J.d.C.)
| | - Paula I. Buonfiglio
- Laboratory of Physiology and Genetics of Hearing, Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres”, Consejo Nacional de Investigaciones Científicas y Técnicas, Vuelta de Obligado 2490, Ciudad Autónoma de Buenos Aires C1428ADN, Argentina; (P.I.B.); (A.B.E.)
| | - Irene García-Vaquero
- Servicio de Genética, Hospital Universitario Ramón y Cajal, 28034 Madrid, Spain; (M.D.-R.); (L.R.-P.); (I.G.-V.); (E.G.-R.); (M.G.); (M.V.); (M.M.); (M.A.M.-P.); (F.J.d.C.)
| | - Elena Gómez-Rosas
- Servicio de Genética, Hospital Universitario Ramón y Cajal, 28034 Madrid, Spain; (M.D.-R.); (L.R.-P.); (I.G.-V.); (E.G.-R.); (M.G.); (M.V.); (M.M.); (M.A.M.-P.); (F.J.d.C.)
| | - Marina Goñi
- Servicio de Genética, Hospital Universitario Ramón y Cajal, 28034 Madrid, Spain; (M.D.-R.); (L.R.-P.); (I.G.-V.); (E.G.-R.); (M.G.); (M.V.); (M.M.); (M.A.M.-P.); (F.J.d.C.)
| | - Manuela Villamar
- Servicio de Genética, Hospital Universitario Ramón y Cajal, 28034 Madrid, Spain; (M.D.-R.); (L.R.-P.); (I.G.-V.); (E.G.-R.); (M.G.); (M.V.); (M.M.); (M.A.M.-P.); (F.J.d.C.)
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 28034 Madrid, Spain
| | - Matías Morín
- Servicio de Genética, Hospital Universitario Ramón y Cajal, 28034 Madrid, Spain; (M.D.-R.); (L.R.-P.); (I.G.-V.); (E.G.-R.); (M.G.); (M.V.); (M.M.); (M.A.M.-P.); (F.J.d.C.)
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 28034 Madrid, Spain
| | - Miguel A. Moreno-Pelayo
- Servicio de Genética, Hospital Universitario Ramón y Cajal, 28034 Madrid, Spain; (M.D.-R.); (L.R.-P.); (I.G.-V.); (E.G.-R.); (M.G.); (M.V.); (M.M.); (M.A.M.-P.); (F.J.d.C.)
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 28034 Madrid, Spain
| | - Ana B. Elgoyhen
- Laboratory of Physiology and Genetics of Hearing, Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres”, Consejo Nacional de Investigaciones Científicas y Técnicas, Vuelta de Obligado 2490, Ciudad Autónoma de Buenos Aires C1428ADN, Argentina; (P.I.B.); (A.B.E.)
- Instituto de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires C1121ABG, Argentina
| | - Francisco J. del Castillo
- Servicio de Genética, Hospital Universitario Ramón y Cajal, 28034 Madrid, Spain; (M.D.-R.); (L.R.-P.); (I.G.-V.); (E.G.-R.); (M.G.); (M.V.); (M.M.); (M.A.M.-P.); (F.J.d.C.)
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 28034 Madrid, Spain
| | - Viviana Dalamón
- Laboratory of Physiology and Genetics of Hearing, Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres”, Consejo Nacional de Investigaciones Científicas y Técnicas, Vuelta de Obligado 2490, Ciudad Autónoma de Buenos Aires C1428ADN, Argentina; (P.I.B.); (A.B.E.)
| | - Ignacio del Castillo
- Servicio de Genética, Hospital Universitario Ramón y Cajal, 28034 Madrid, Spain; (M.D.-R.); (L.R.-P.); (I.G.-V.); (E.G.-R.); (M.G.); (M.V.); (M.M.); (M.A.M.-P.); (F.J.d.C.)
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 28034 Madrid, Spain
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Xiang J, Peng J, Sun X, Lin Z, Li D, Ye H, Wang S, Bai Y, Wang X, Du P, Gao Y, Sun J, Pan S, Peng Z. The Next Generation of Population-Based DFNB16 Carrier Screening and Diagnosis: STRC Copy-Number Variant Analysis from Genome Sequencing Data. Clin Chem 2023:7174048. [PMID: 37207672 DOI: 10.1093/clinchem/hvad046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 03/28/2023] [Indexed: 05/21/2023]
Abstract
BACKGROUND Deafness, autosomal recessive 16 (DFNB16) is caused by compound heterozygous or homozygous variants in STRC and is the second most common form of genetic hearing loss. Due to the nearly identical sequences of STRC and the pseudogene STRCP1, analysis of this region is challenging in clinical testing. METHODS We developed a method that accurately identifies the copy number of STRC and STRCP1 using standard short-read genome sequencing. Then, we used whole genome sequencing (WGS) data to investigate the population distribution of STRC copy number in 6813 neonates and the correlation between STRC and STRCP1 copy number. RESULTS The comparison of WGS results with multiplex ligation-dependent probe amplification demonstrated high sensitivity (100%; 95% CI, 97.5%-100%) and specificity (98.8%; 95% CI, 97.7%-99.5%) in detecting heterozygous deletion of STRC from short-read genome sequencing data. The population analysis revealed that 5.22% of the general population has STRC copy number changes, almost half of which (2.33%; 95% CI, 1.99%-2.72%) were clinically significant, including heterozygous and homozygous STRC deletions. There was a strong inverse correlation between STRC and STRCP1 copy number. CONCLUSIONS We developed a novel and reliable method to determine STRC copy number based on standard short-read based WGS data. Incorporating this method into analytic pipelines would improve the clinical utility of WGS in the screening and diagnosis of hearing loss. Finally, we provide population-based evidence of pseudogene-mediated gene conversions between STRC and STRCP1.
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Affiliation(s)
- Jiale Xiang
- BGI Genomics, BGI-Shenzhen, Shenzhen 518083, China
| | - Jiguang Peng
- BGI Genomics, BGI-Shenzhen, Shenzhen 518083, China
| | | | - Zibin Lin
- BGI Genomics, BGI-Shenzhen, Shenzhen 518083, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Dongdong Li
- BGI Genomics, BGI-Shenzhen, Shenzhen 518083, China
| | - Haodong Ye
- BGI Genomics, BGI-Shenzhen, Shenzhen 518083, China
| | - Sibao Wang
- Heart Center, Qingdao Women and Children's Hospital, Qingdao University, Qingdao 266034, China
| | - Yushi Bai
- Guangdong Zhongyi Forensic Science Center, Shenzhen 518000, China
| | | | - Peina Du
- BGI-Qingdao, BGI-Shenzhen, Qingdao 266555, China
| | - Ya Gao
- BGI-Shenzhen, Shenzhen 518083, China
| | - Jun Sun
- BGI Genomics, BGI-Shenzhen, Shenzhen 518083, China
- Tianjin Medical Laboratory, BGI-Tianjin, BGI-Shenzhen, Tianjin 300308, China
| | - Silin Pan
- Heart Center, Qingdao Women and Children's Hospital, Qingdao University, Qingdao 266034, China
| | - Zhiyu Peng
- BGI Genomics, BGI-Shenzhen, Shenzhen 518083, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
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Clabout T, Maes L, Acke F, Wuyts W, Van Schil K, Coucke P, Janssens S, De Leenheer E. Negative Molecular Diagnostics in Non-Syndromic Hearing Loss: What Next? Genes (Basel) 2022; 14:genes14010105. [PMID: 36672845 PMCID: PMC9859074 DOI: 10.3390/genes14010105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/23/2022] [Accepted: 12/26/2022] [Indexed: 12/31/2022] Open
Abstract
Congenital hearing loss has an impact on almost every facet of life. In more than 50% of cases, a genetic cause can be identified. Currently, extensive genetic testing is available, although the etiology of some patients with obvious familial hearing loss remains unknown. We selected a cohort of mutation-negative patients to optimize the diagnostic yield for genetic hearing impairment. In this retrospective study, 21 patients (17 families) with negative molecular diagnostics for non-syndromic hearing loss (gene panel analysis) were included based on a positive family history with a similar type of hearing loss. Additional genetic testing was performed using a whole exome sequencing panel (WESHL panel v2.0) in four families with the strongest likelihood of genetic hearing impairment. In this cohort (n = 21), the severity of hearing loss was most commonly moderate (52%). Additional genetic testing revealed pathogenic copy number variants in the STRC gene in two families. In summary, regular re-evaluation of hearing loss patients with presumably genetic etiology after negative molecular diagnostics is recommended, as we might miss newly discovered deafness genes. The switch from gene panel analysis to whole exome sequencing or whole genome sequencing for the testing of congenital hearing loss seems promising.
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Affiliation(s)
- Thomas Clabout
- Faculty of Medicine and Health Sciences, Ghent University, Corneel Heymanslaan 10, B-9000 Ghent, Belgium
| | - Laurence Maes
- Faculty of Medicine and Health Sciences, Ghent University, Corneel Heymanslaan 10, B-9000 Ghent, Belgium
| | - Frederic Acke
- Department of Otorhinolaryngology, Ghent University Hospital, Corneel Heymanslaan 10, B-9000 Ghent, Belgium
| | - Wim Wuyts
- Center of Medical Genetics, Antwerp University Hospital and University of Antwerp, Prins Boudewijnlaan 43, B-2650 Edegem, Belgium
| | - Kristof Van Schil
- Center of Medical Genetics, Antwerp University Hospital and University of Antwerp, Prins Boudewijnlaan 43, B-2650 Edegem, Belgium
| | - Paul Coucke
- Center for Medical Genetics, Ghent University, Corneel Heymanslaan 10, B-9000 Ghent, Belgium
| | - Sandra Janssens
- Center for Medical Genetics, Ghent University, Corneel Heymanslaan 10, B-9000 Ghent, Belgium
| | - Els De Leenheer
- Department of Otorhinolaryngology, Ghent University Hospital, Corneel Heymanslaan 10, B-9000 Ghent, Belgium
- Correspondence: ; Tel.: +32-93322332
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Zhang W, Song J, Tong B, Ma M, Guo L, Yuan Y, Yang J. Identification of a novel CNV at the EYA4 gene in a Chinese family with autosomal dominant nonsyndromic hearing loss. BMC Med Genomics 2022; 15:113. [PMID: 35578334 PMCID: PMC9109401 DOI: 10.1186/s12920-022-01269-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 05/10/2022] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Hereditary hearing loss is a heterogeneous class of disorders that exhibits various patterns of inheritance and involves many genes. Variants in the EYA4 gene in DFNA10 are known to lead to postlingual, progressive, autosomal dominant nonsyndromic hereditary hearing loss. PATIENTS AND METHODS We collected a four-generation Chinese family with autosomal-dominant nonsyndromic hearing loss (ADNSHL). We applied targeted next-generation sequencing (TNGS) in three patients of this pedigree and whole-genome sequencing (WGS) in the proband. The intrafamilial cosegregation of the variant and the deafness phenotype were confirmed by PCR, gap-PCR and Sanger sequencing. RESULTS A novel CNV deletion at 6q23 in exons 8-11 of the EYA4 gene with a 10 bp insertion was identified by TNGS and WGS and segregated with the ADNSHL phenotypes. CONCLUSIONS Our results expanded the variant spectrum and genotype‒phenotype correlation of the EYA4 gene and autosomal dominant nonsyndromic hereditary hearing loss in Chinese Han individuals. WGS is an accurate and effective method for verifying the genomic features of CNVs.
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Affiliation(s)
- Weixun Zhang
- Department of Otology and Skull Base Surgery, Eye Ear Nose and Throat Hospital, Fudan University, Shanghai, 200031, China
- Shanghai Clinical Medical Center of Hearing Medicine, Shanghai, 200031, China
- Key Laboratory of Hearing Medicine of National Health Commission of the People's Republic of China, Shanghai, 20031, China
- Research Institute of Otolaryngology, Fudan University, Shanghai, 200031, China
- Lateral Skull Base Diagnosis and Treatment Center, Eye Ear Nose and Throat Hospital, Fudan University, Shanghai, 200031, China
| | - Jing Song
- Department of Otology and Skull Base Surgery, Eye Ear Nose and Throat Hospital, Fudan University, Shanghai, 200031, China
- Shanghai Clinical Medical Center of Hearing Medicine, Shanghai, 200031, China
- Key Laboratory of Hearing Medicine of National Health Commission of the People's Republic of China, Shanghai, 20031, China
- Research Institute of Otolaryngology, Fudan University, Shanghai, 200031, China
| | - Busheng Tong
- Department of Otorhinolaryngology Head and Neck Surgery, First Affiliated Hospital of Anhui Medical University, Jixi Road 218, Hefei, 230022, Anhui, China
| | - Mengye Ma
- Department of Otology and Skull Base Surgery, Eye Ear Nose and Throat Hospital, Fudan University, Shanghai, 200031, China
- Shanghai Clinical Medical Center of Hearing Medicine, Shanghai, 200031, China
- Key Laboratory of Hearing Medicine of National Health Commission of the People's Republic of China, Shanghai, 20031, China
- Research Institute of Otolaryngology, Fudan University, Shanghai, 200031, China
| | - Luo Guo
- Department of Otology and Skull Base Surgery, Eye Ear Nose and Throat Hospital, Fudan University, Shanghai, 200031, China
- Shanghai Clinical Medical Center of Hearing Medicine, Shanghai, 200031, China
- Key Laboratory of Hearing Medicine of National Health Commission of the People's Republic of China, Shanghai, 20031, China
| | - Yasheng Yuan
- Department of Otology and Skull Base Surgery, Eye Ear Nose and Throat Hospital, Fudan University, Shanghai, 200031, China.
- Shanghai Clinical Medical Center of Hearing Medicine, Shanghai, 200031, China.
- Key Laboratory of Hearing Medicine of National Health Commission of the People's Republic of China, Shanghai, 20031, China.
- Research Institute of Otolaryngology, Fudan University, Shanghai, 200031, China.
- Lateral Skull Base Diagnosis and Treatment Center, Eye Ear Nose and Throat Hospital, Fudan University, Shanghai, 200031, China.
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, 83 Fenyang Road, Xuhui District, Shanghai, China.
| | - Juanmei Yang
- Department of Otology and Skull Base Surgery, Eye Ear Nose and Throat Hospital, Fudan University, Shanghai, 200031, China.
- Shanghai Clinical Medical Center of Hearing Medicine, Shanghai, 200031, China.
- Key Laboratory of Hearing Medicine of National Health Commission of the People's Republic of China, Shanghai, 20031, China.
- Research Institute of Otolaryngology, Fudan University, Shanghai, 200031, China.
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, 83 Fenyang Road, Xuhui District, Shanghai, China.
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Mutai H, Momozawa Y, Kamatani Y, Nakano A, Sakamoto H, Takiguchi T, Nara K, Kubo M, Matsunaga T. Whole exome analysis of patients in Japan with hearing loss reveals high heterogeneity among responsible and novel candidate genes. Orphanet J Rare Dis 2022; 17:114. [PMID: 35248088 PMCID: PMC8898489 DOI: 10.1186/s13023-022-02262-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 02/20/2022] [Indexed: 11/16/2022] Open
Abstract
Background Heterogeneous genetic loci contribute to hereditary hearing loss; more than 100 deafness genes have been identified, and the number is increasing. To detect pathogenic variants in multiple deafness genes, in addition to novel candidate genes associated with hearing loss, whole exome sequencing (WES), followed by analysis prioritizing genes categorized in four tiers, were applied.
Results Trios from families with non-syndromic or syndromic hearing loss (n = 72) were subjected to WES. After segregation analysis and interpretation according to American College of Medical Genetics and Genomics guidelines, candidate pathogenic variants in 11 previously reported deafness genes (STRC, MYO15A, CDH23, PDZD7, PTPN11, SOX10, EYA1, MYO6, OTOF, OTOG, and ZNF335) were identified in 21 families. Discrepancy between pedigree inheritance and genetic inheritance was present in one family. In addition, eight genes (SLC12A2, BAIAP2L2, HKDC1, SVEP1, CACNG1, GTPBP4, PCNX2, and TBC1D8) were screened as single candidate genes in 10 families. Conclusions Our findings demonstrate that four-tier assessment of WES data is efficient and can detect novel candidate genes associated with hearing loss, in addition to pathogenic variants of known deafness genes. Supplementary Information The online version contains supplementary material available at 10.1186/s13023-022-02262-4.
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Evaluation of copy number variants for genetic hearing loss: a review of current approaches and recent findings. Hum Genet 2021; 141:387-400. [PMID: 34811589 DOI: 10.1007/s00439-021-02365-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 09/02/2021] [Indexed: 01/22/2023]
Abstract
Structural variation includes a change in copy number, orientation, or location of a part of the genome. Copy number variants (CNVs) are a common cause of genetic hearing loss, comprising nearly 20% of diagnosed cases. While large deletions involving the gene STRC are the most common pathogenic CNVs, a significant proportion of known hearing loss genes also contain pathogenic CNVs. In this review, we provide an overview of currently used methods for detection of CNVs in genes known to cause hearing loss including molecular techniques such as multiplex ligation probe amplification (MLPA) and digital droplet polymerase chain reaction (ddPCR), array-CGH and single-nucleotide polymorphism (SNP) arrays, as well as techniques for detection of CNVs using next-generation sequencing data analysis including targeted gene panel, exome, and genome sequencing data. In addition, in this review, we compile published data on pathogenic hearing loss CNVs to provide an up-to-date overview. We show that CNVs have been identified in 29 different non-syndromic hearing loss genes. An understanding of the contribution of CNVs to genetic hearing loss is critical to the current diagnosis of hearing loss and is crucial for future gene therapies. Thus, evaluation for CNVs is required in any modern pipeline for genetic diagnosis of hearing loss.
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Usami SI, Nishio SY. The genetic etiology of hearing loss in Japan revealed by the social health insurance-based genetic testing of 10K patients. Hum Genet 2021; 141:665-681. [PMID: 34599366 PMCID: PMC9035015 DOI: 10.1007/s00439-021-02371-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 09/14/2021] [Indexed: 11/28/2022]
Abstract
Etiological studies have shown genetic disorders to be a major cause of sensorineural hearing loss, but there are a limited number of comprehensive etiological reports based on genetic analysis. In the present study, the same platform using a diagnostic DNA panel carrying 63 deafness genes and the same filtering algorithm were applied to 10,047 samples obtained from social health insurance-based genetic testing of hearing loss. The most remarkable result obtained in this comprehensive study was that the data first clarified the genetic epidemiology from congenital/early-onset deafness to late-onset hearing loss. The overall diagnostic rate was 38.8%, with the rate differing for each age group; 48.6% for the congenital/early-onset group (~5y.o.), 33.5% for the juvenile/young adult-onset group, and 18.0% for the 40+ y.o. group. Interestingly, each group showed a different kind of causative gene. With regard to the mutational spectra, there are certain recurrent variants that may be due to founder effects or hot spots. A series of haplotype studies have shown many recurrent variants are due to founder effects, which is compatible with human migration. It should be noted that, regardless of differences in the mutational spectrum, the clinical characteristics caused by particular genes can be considered universal. This comprehensive review clarified the detailed clinical characteristics (onset age, severity, progressiveness, etc.) of hearing loss caused by each gene, and will provide useful information for future clinical application, including genetic counseling and selection of appropriate interventions.
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Affiliation(s)
- Shin-Ichi Usami
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621, Japan.
| | - Shin-Ya Nishio
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621, Japan
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CNV Detection from Exome Sequencing Data in Routine Diagnostics of Rare Genetic Disorders: Opportunities and Limitations. Genes (Basel) 2021; 12:genes12091427. [PMID: 34573409 PMCID: PMC8472439 DOI: 10.3390/genes12091427] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 09/08/2021] [Accepted: 09/09/2021] [Indexed: 12/15/2022] Open
Abstract
To assess the potential of detecting copy number variations (CNVs) directly from exome sequencing (ES) data in diagnostic settings, we developed a CNV-detection pipeline based on ExomeDepth software and applied it to ES data of 450 individuals. Initially, only CNVs affecting genes in the requested diagnostic gene panels were scored and tested against arrayCGH results. Pathogenic CNVs were detected in 18 individuals. Most detected CNVs were larger than 400 kb (11/18), but three individuals had small CNVs impacting one or a few exons only and were thus not detectable by arrayCGH. Conversely, two pathogenic CNVs were initially missed, as they impacted genes not included in the original gene panel analysed, and a third one was missed as it was in a poorly covered region. The overall combined diagnostic rate (SNVs + CNVs) in our cohort was 36%, with wide differences between clinical domains. We conclude that (1) the ES-based CNV pipeline detects efficiently large and small pathogenic CNVs, (2) the detection of CNV relies on uniformity of sequencing and good coverage, and (3) in patients who remain unsolved by the gene panel analysis, CNV analysis should be extended to all captured genes, as diagnostically relevant CNVs may occur everywhere in the genome.
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Ishino T, Ogawa Y, Sonoyama T, Taruya T, Kono T, Hamamoto T, Ueda T, Takeno S, Moteki H, Nishio SY, Usami SI, Nagano Y, Yoshimura A, Yoshikawa K, Kato M, Ichimoto M, Watanabe R. Identification of a Novel Copy Number Variation of EYA4 Causing Autosomal Dominant Non-syndromic Hearing Loss. Otol Neurotol 2021; 42:e866-e874. [PMID: 33859130 DOI: 10.1097/mao.0000000000003169] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Eyes absent 4 (EYA4) is the causative gene of autosomal dominant non-syndromic hereditary hearing loss, DFNA10. We aimed to identify a copy number variation of EYA4 in a non-syndromic sensory neural hearing loss pedigree. FAMILY AND CLINICAL EVALUATION A Japanese family showing late-onset and progressive hearing loss was evaluated. A pattern of autosomal dominant inheritance of hearing loss was recognized in the pedigree. No cardiac disease was observed in any of the individuals. METHODS Targeted exon sequencing was performed using massively parallel DNA sequencing (MPS) analysis. Scanning of the array comparative genomic hybridization (aCGH) was completed and the copy number variation (CNV) data from the aCGH analysis was confirmed by matching all CNV calls with MPS analysis. Breakpoint detection was performed by whole-genome sequencing and direct sequencing. Sequencing results were examined, and co-segregation analysis of hearing loss was completed. RESULTS We identified a novel hemizygous indel that showed CNV in the EYA4 gene from the position 133,457,057 to 133,469,892 on chromosome 6 (build GRCh38/hg38) predicted as p.(Val124_Pro323del), and that was segregated with post-lingual and progressive autosomal dominant sensorineural hearing loss by aCGH analysis. CONCLUSION Based on the theory of genotype-phenotype correlation with EYA4 mutations in terms of hearing loss and comorbid dilated cardiomyopathy, the region of amino acids 124 to 343 is hypothesized not to be the pathogenic region causing dilated cardiomyopathy. Additionally, the theory of genotype-phenotype correlation about the prevalence of dilated cardiomyopathy is thought to be rejected because of no correlation of deleted amino acid region with the prevalence of dilated cardiomyopathy. These results will help expand the research on both the coordination of cochlear transcriptional regulation and normal cardiac gene regulation via EYA4 transcripts and provide information on the genotype-phenotype correlations of DFNA10 hearing loss.
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Affiliation(s)
- Takashi Ishino
- Department of Otorhinolaryngology, Head and Neck Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University
| | - Yui Ogawa
- Department of Otorhinolaryngology, Head and Neck Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University
| | - Toru Sonoyama
- Department of Otorhinolaryngology, Head and Neck Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University
| | - Takayuki Taruya
- Department of Otorhinolaryngology, Head and Neck Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University
| | - Takashi Kono
- Department of Otorhinolaryngology, Head and Neck Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University
| | - Takao Hamamoto
- Department of Otorhinolaryngology, Head and Neck Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University
| | - Tsutomu Ueda
- Department of Otorhinolaryngology, Head and Neck Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University
| | - Sachio Takeno
- Department of Otorhinolaryngology, Head and Neck Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University
| | - Hideaki Moteki
- Department of Otorhinolaryngology, Shinshu University School of Medicine
| | - Shin-Ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine
| | - Shin-Ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine
| | - Yuka Nagano
- Division of Rehabilitation, Department of Clinical Practice and Support, Hiroshima University, Minami-ku, Hiroshima, Japan
| | - Akiko Yoshimura
- Division of Rehabilitation, Department of Clinical Practice and Support, Hiroshima University, Minami-ku, Hiroshima, Japan
| | - Kohei Yoshikawa
- Division of Rehabilitation, Department of Clinical Practice and Support, Hiroshima University, Minami-ku, Hiroshima, Japan
| | - Mikako Kato
- Division of Rehabilitation, Department of Clinical Practice and Support, Hiroshima University, Minami-ku, Hiroshima, Japan
| | - Masaya Ichimoto
- Division of Rehabilitation, Department of Clinical Practice and Support, Hiroshima University, Minami-ku, Hiroshima, Japan
| | - Rina Watanabe
- Division of Rehabilitation, Department of Clinical Practice and Support, Hiroshima University, Minami-ku, Hiroshima, Japan
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10
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Laurent S, Gehrig C, Nouspikel T, Amr SS, Oza A, Murphy E, Vannier A, Béna FS, Carminho-Rodrigues MT, Blouin JL, Cao Van H, Abramowicz M, Paoloni-Giacobino A, Guipponi M. Molecular characterization of pathogenic OTOA gene conversions in hearing loss patients. Hum Mutat 2021; 42:373-377. [PMID: 33492714 DOI: 10.1002/humu.24167] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 12/02/2020] [Accepted: 12/16/2020] [Indexed: 11/11/2022]
Abstract
Bi-allelic loss-of-function variants of OTOA are a well-known cause of moderate-to-severe hearing loss. Whereas non-allelic homologous recombination-mediated deletions of the gene are well known, gene conversions to pseudogene OTOAP1 have been reported in the literature but never fully described nor their pathogenicity assessed. Here, we report two unrelated patients with moderate hearing-loss, who were compound heterozygotes for a converted allele and a deletion of OTOA. The conversions were initially detected through sequencing depths anomalies at the OTOA locus after exome sequencing, then confirmed with long range polymerase chain reactions. Both conversions lead to loss-of-function by introducing a premature stop codon in exon 22 (p.Glu787*). Using genomic alignments and long read nanopore sequencing, we found that the two probands carry stretches of converted DNA of widely different lengths (at least 9 kbp and around 900 bp, respectively).
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Affiliation(s)
- Sacha Laurent
- Department of Diagnostic, Genetic Medicine Unit, University Hospitals of Geneva, Geneva, Switzerland
| | - Corinne Gehrig
- Department of Diagnostic, Genetic Medicine Unit, University Hospitals of Geneva, Geneva, Switzerland
| | - Thierry Nouspikel
- Department of Diagnostic, Genetic Medicine Unit, University Hospitals of Geneva, Geneva, Switzerland
| | - Sami S Amr
- Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine, Cambridge, Massachusetts, USA
| | - Andrea Oza
- Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine, Cambridge, Massachusetts, USA
| | - Elissa Murphy
- Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine, Cambridge, Massachusetts, USA
| | - Anne Vannier
- Department of Diagnostic, Genetic Medicine Unit, University Hospitals of Geneva, Geneva, Switzerland
| | - Frédérique Sloan Béna
- Department of Diagnostic, Genetic Medicine Unit, University Hospitals of Geneva, Geneva, Switzerland.,Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland
| | | | - Jean-Louis Blouin
- Department of Diagnostic, Genetic Medicine Unit, University Hospitals of Geneva, Geneva, Switzerland.,Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland
| | - Hélène Cao Van
- Department of Otorhinolaryngology, Head and Neck Surgery, Pediatric Otolaryngology Unit, University Hospitals of Geneva, Geneva, Switzerland
| | - Marc Abramowicz
- Department of Diagnostic, Genetic Medicine Unit, University Hospitals of Geneva, Geneva, Switzerland.,Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland
| | - Ariane Paoloni-Giacobino
- Department of Diagnostic, Genetic Medicine Unit, University Hospitals of Geneva, Geneva, Switzerland.,Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland
| | - Michel Guipponi
- Department of Diagnostic, Genetic Medicine Unit, University Hospitals of Geneva, Geneva, Switzerland.,Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland
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11
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Rentas S, Abou Tayoun A. Utility of droplet digital PCR and NGS-based CNV clinical assays in hearing loss diagnostics: current status and future prospects. Expert Rev Mol Diagn 2021; 21:213-221. [PMID: 33554673 DOI: 10.1080/14737159.2021.1887731] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Introduction: Genetic variants in over 100 genes can cause non-syndromic hearing loss (NSHL). Comprehensive diagnostic testing of these genes requires detecting pathogenic sequence and copy number alterations with economical, scalable and sensitive assays. Here we discuss best practices and effective testing algorithms for hearing-loss-related genes with special emphasis on detection of copy number variants.Areas covered: We review studies that used next-generation sequencing (NGS), chromosomal microarrays, droplet digital PCR (ddPCR), and multiplex ligation-dependent probe amplification (MLPA) for the diagnosis of NSHL. We specifically focus on unique and recurrent copy number changes that affect the GJB2 and STRC genes, two of the most common causes of NSHL.Expert opinion: NGS panels and exome sequencing can detect most pathogenic sequence and copy number variants that cause NSHL; however, GJB2 and STRC currently require additional assays to capture all pathogenic copy number variants. Adoption of genome sequencing may simplify diagnostic workflows, but further investigational studies will be required to evaluate its clinical efficacy.
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Affiliation(s)
- Stefan Rentas
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Ahmad Abou Tayoun
- Al Jalila Genomics Center, Al Jalila Children's Specialty Hospital, Dubai, UAE.,Department of Genetics, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai, UAE
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12
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Clinical features of hearing loss caused by STRC gene deletions/mutations in Russian population. Int J Pediatr Otorhinolaryngol 2020; 138:110247. [PMID: 32705992 DOI: 10.1016/j.ijporl.2020.110247] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/02/2020] [Accepted: 07/02/2020] [Indexed: 12/29/2022]
Abstract
UNLABELLED Congenital sensorineural hearing loss is related to mutations in numerous genes encoding the structures of the inner ear in majority of the cases. Mutations in GJB2 gene are the most frequently identified causes of congenital nonsyndromal hearing loss. GJB2 gene testing became a routine clinical tool. For GJB2-negative patients new genetic approaches including methods based on new generation sequencing give a chance to identify mutations in other genes. The frequent reason of mild-to-moderate hearing loss such as the deletions/mutations of the gene STRC encoding stereocilin protein were recognized (OMIM: 606440). OBJECTIVES To evaluate the audiological features in hearing impaired patients with deletions and point mutations in the STRC gene. PATIENTS AND METHODS The group of 28 patients from 21 unrelated families with pathological mutations in the STRC gene underwent audiological examination. The description and analysis of the results of full audiological examination was provided. RESULTS All patients initially had bilateral nonsyndromal sensorineural hearing loss. Among 11 homozygotes of large deletion harboring STRC to CATSPER2 genes were 7 male individuals indicating the presence of male infertility syndrome. In general, 7 children failed audiological screening and 4 children underwent audiological assessment in the age of 3 and 6 months. The most frequently hearing thresholds were registered between 35 and 55 dB that corresponds to mild-to-moderate hearing impairment. The average age of diagnostics was 7.9 years (ranged from 3 months to 45 years). In the majority of patients the audiological profiles were flat or descending with elevation of thresholds at middle and high frequencies and relatively preserved thresholds at low frequencies. Hearing thresholds are symmetric and stable with age. CONCLUSION STRC-linked hearing loss is congenital, of mild and moderate severity. Special clinical and genetic approach for children who failed newborn hearing screening with mild-to-moderate hearing loss is necessary.
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13
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Lu X, Wang Q, Gu H, Zhang X, Qi Y, Liu Y. Whole exome sequencing identified a second pathogenic variant in HOMER2 for autosomal dominant non-syndromic deafness. Clin Genet 2019; 94:419-428. [PMID: 30047143 DOI: 10.1111/cge.13422] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Revised: 06/26/2018] [Accepted: 07/19/2018] [Indexed: 12/11/2022]
Abstract
Hearing loss is one of the most common sensory disorders worldwide, and about half of all occurrences are attributable to genetic factors. Here, we have identified a novel pathogenic variant in HOMER2 in a Chinese family with autosomal dominant, non-syndromic hearing loss. This is the second family reported globally with hearing loss caused by a variant in HOMER2. The pathogenic variant c.840_841insC in HOMER2 (NM_199330), segregating with the hearing-loss phenotype in the family, leads to a premature stop codon producing a truncated protein. The coiled-coil domain in the C-terminal of HOMER2 protein is essential for protein multimerization and HOMER2-CDC42 interaction. We compared the phenotypes in the two families and found that hearing impairment in this Chinese family was more severe. Furthermore, we found that the ability of this insertion mutant type HOMER2 (HOMER2MU ) to multimerize decreased more significantly than wild-type HOMER2 (HOMER2WT ) and the reported c.554G>C (NM_004839) mutant HOMER2. HOMER2MU protein tended to be distributed in a diffuse manner, whereas HOMER2WT and the reported mutant HOMER2 tended to cluster together. Our research provides a validating second family for variants in HOMER2 causing non-syndromic sensorineural hearing loss. HOMER2 homo-/hetero-multimerization might be the first step in exerting its normal function.
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Affiliation(s)
- X Lu
- Department of Otolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing, China
| | - Q Wang
- Department of Otolaryngology, Head and Neck Surgery, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - H Gu
- Department of Otolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing, China
| | - X Zhang
- Department of Otolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing, China
| | - Y Qi
- Department of Central Laboratory, Peking University First Hospital, Beijing, China
| | - Y Liu
- Department of Otolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing, China
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14
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Mid-Frequency Hearing Loss Is Characteristic Clinical Feature of OTOA-Associated Hearing Loss. Genes (Basel) 2019; 10:genes10090715. [PMID: 31527525 PMCID: PMC6770988 DOI: 10.3390/genes10090715] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 09/09/2019] [Accepted: 09/12/2019] [Indexed: 12/03/2022] Open
Abstract
The OTOA gene (Locus: DFNB22) is reported to be one of the causative genes for non-syndromic autosomal recessive hearing loss. The copy number variations (CNVs) identified in this gene are also known to cause hearing loss, but have not been identified in Japanese patients with hearing loss. Furthermore, the clinical features of OTOA-associated hearing loss have not yet been clarified. In this study, we performed CNV analyses of a large Japanese hearing loss cohort, and identified CNVs in 234 of 2262 (10.3%, 234/2262) patients with autosomal recessive hearing loss. Among the identified CNVs, OTOA gene-related CNVs were the second most frequent (0.6%, 14/2262). Among the 14 cases, 2 individuals carried OTOA homozygous deletions, 4 carried heterozygous deletions with single nucleotide variants (SNVs) in another allele. Additionally, 1 individual with homozygous SNVs in the OTOA gene was also identified. Finally, we identified 7 probands with OTOA-associated hearing loss, so that its prevalence in Japanese patients with autosomal recessive hearing loss was calculated to be 0.3% (7/2262). As novel clinical features identified in this study, the audiometric configurations of patients with OTOA-associated hearing loss were found to be mid-frequency. This is the first study focused on the detailed clinical features of hearing loss caused by this gene mutation and/or gene deletion.
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15
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Ito T, Kawashima Y, Fujikawa T, Honda K, Makabe A, Kitamura K, Tsutsumi T. Rapid screening of copy number variations in STRC by droplet digital PCR in patients with mild-to-moderate hearing loss. Hum Genome Var 2019; 6:41. [PMID: 31645979 PMCID: PMC6804619 DOI: 10.1038/s41439-019-0075-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 07/31/2019] [Accepted: 08/01/2019] [Indexed: 11/09/2022] Open
Abstract
Copy number variations (CNVs) are commonly reported in STRC, the causal gene for DFNB16. Various techniques are used clinically for CNV detection, and droplet digital PCR (ddPCR) provides highly precise absolute quantification of DNA copy number. We aimed to validate the feasibility and efficiency of ddPCR in combination with long-range PCR (LR-PCR) in identifying CNVs and mutations in STRC. Additionally, we determined the frequency of CNVs and mutations in STRC in Japanese patients with mild-to-moderate hearing loss. We evaluated 84 unrelated Japanese patients with mild-to-moderate bilateral idiopathic or autosomal recessive nonsyndromic sensorineural hearing loss. The ratio of STRC copy number to the copy number of the internal control RPP30 ranged from 0.949 to 1.009 (0.989 ± 0.017) in 77 patients; it ranged from 0.484 to 0.538 (0.509 ± 0.024) in five patients and was 0.000 in two patients, indicating heterozygous and homozygous deletions, respectively. The copy number deletion prevalence rates were 7.7% and 0.9% in the patients and healthy controls, respectively. In combination with LR-PCR, ddPCR revealed that at least three patients (3.6%) had STRC-related hearing loss. Detecting STRC CNVs by ddPCR was rapid, precise, and cost-effective and facilitated the identification of STRC CNVs.
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Affiliation(s)
- Taku Ito
- 1Department of Otorhinolaryngology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yoshiyuki Kawashima
- 1Department of Otorhinolaryngology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Taro Fujikawa
- 1Department of Otorhinolaryngology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Keiji Honda
- 1Department of Otorhinolaryngology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Ayane Makabe
- 1Department of Otorhinolaryngology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Ken Kitamura
- 1Department of Otorhinolaryngology, Tokyo Medical and Dental University, Tokyo, Japan.,Department of Otorhinolaryngology, Head and Neck Surgery, Chigasaki Chuo Hospital, Chigasaki, Japan
| | - Takeshi Tsutsumi
- 1Department of Otorhinolaryngology, Tokyo Medical and Dental University, Tokyo, Japan
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16
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Yokota Y, Moteki H, Nishio SY, Yamaguchi T, Wakui K, Kobayashi Y, Ohyama K, Miyazaki H, Matsuoka R, Abe S, Kumakawa K, Takahashi M, Sakaguchi H, Uehara N, Ishino T, Kosho T, Fukushima Y, Usami SI. Frequency and clinical features of hearing loss caused by STRC deletions. Sci Rep 2019; 9:4408. [PMID: 30867468 PMCID: PMC6416315 DOI: 10.1038/s41598-019-40586-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Accepted: 02/19/2019] [Indexed: 12/04/2022] Open
Abstract
Sensorineural hearing loss is a common deficit and mainly occurs due to genetic factors. Recently, copy number variants (CNVs) in the STRC gene have also been recognized as a major cause of genetic hearing loss. We investigated the frequency of STRC deletions in the Japanese population and the characteristics of associated hearing loss. For CNV analysis, we employed a specialized method of Ion AmpliSeqTM sequencing, and confirmed the CNV results via custom array comparative genomic hybridization. We identified 17 probands with STRC homozygous deletions. The prevalence of STRC homozygous deletions was 1.7% in the hearing loss population overall, and 4.3% among mild-to-moderate hearing loss patients. A 2.63% carrier deletion rate was identified in both the hearing loss and the control population with normal hearing. In conclusion, our results show that STRC deletions are the second most common cause of mild-to-moderate hearing loss after the GJB2 gene, which accounts for the majority of genetic hearing loss. The phenotype of hearing loss is congenital and appears to be moderate, and is most likely to be stable without deterioration even after the age of 50. The present study highlights the importance of the STRC gene as a major cause of mild-to-moderate hearing loss.
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Affiliation(s)
- Yoh Yokota
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Hideaki Moteki
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan. .,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan.
| | - Shin-Ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan.,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Tomomi Yamaguchi
- Department of Medical Genetics, Shinshu University School of Medicine, Matsumoto, Japan.,Center for Medical Genetics, Shinshu University Hospital, Matsumoto, Japan
| | - Keiko Wakui
- Department of Medical Genetics, Shinshu University School of Medicine, Matsumoto, Japan.,Center for Medical Genetics, Shinshu University Hospital, Matsumoto, Japan
| | - Yumiko Kobayashi
- Department of Otolaryngology-Head & Neck Surgery, Iwate Medical University, Morioka, Japan
| | - Kenji Ohyama
- Department of Otorhinolaryngology, Tohoku Rosai Hospital, Sendai, Japan
| | - Hiromitsu Miyazaki
- Department of Otorhinolaryngology-Head and Neck Surgery, Tohoku University School of Medicine, Sendai, Japan
| | - Rina Matsuoka
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Satoko Abe
- Department of Otorhinolaryngology, Toranomon Hospital, Tokyo, Japan
| | - Kozo Kumakawa
- Department of Otorhinolaryngology, Toranomon Hospital, Tokyo, Japan
| | - Masahiro Takahashi
- Department of Otorhinolaryngology, Head and Neck Surgery, Yokohama City University School of Medicine, Yokohama, Japan.,Department of Otorhinolaryngology, International University of Health and Welfare, Mita Hospital, Tokyo, Japan
| | - Hirofumi Sakaguchi
- Department of Otorhinolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Natsumi Uehara
- Department of Otolaryngology-Head and Neck Surgery, Kobe University School of Medicine, Kobe, Japan
| | - Takashi Ishino
- Department of Otorhinolaryngology, Head and Neck Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Tomoki Kosho
- Department of Medical Genetics, Shinshu University School of Medicine, Matsumoto, Japan.,Center for Medical Genetics, Shinshu University Hospital, Matsumoto, Japan.,Research Center for Support to Advanced Science, Shinshu University, Matsumoto, Japan
| | | | - Shin-Ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan.,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
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17
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Mahfood M, Kamal Eddine Ahmad Mohamed W, Al Mutery A, Tlili A. Clinical Exome Sequencing Identifies a Frameshift Mutation Within the STRC Gene in a United Arab Emirates Family with Profound Nonsyndromic Hearing Loss. Genet Test Mol Biomarkers 2019; 23:204-208. [PMID: 30758234 DOI: 10.1089/gtmb.2018.0264] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
AIMS Autosomal recessive nonsyndromic hearing loss (ARNSHL) is the most common form of hereditary deafness. Despite its frequency, the diagnosis of this disorder continues to be a challenging task given its extreme genetic heterogeneity. The purpose of this study was to identify the causative mutation in a consanguineous United Arab Emirates (UAE) family with ARNSHL. MATERIALS AND METHODS Clinical exome sequencing (CES) followed by segregation analysis via Sanger sequencing was used to identify the causative mutation. In addition, 109 deaf individuals and 50 deafness-free controls from the UAE population were screened for the identified mutation. RESULTS AND DISCUSSION CES identified the STRC frameshift mutation c.4510del (p.Glu1504Argfs*32) as the causative mutation in this family. Moreover, segregation analysis confirmed the above finding. In addition, the absence of this variant in 109 unrelated deaf individuals and 50 healthy controls indicates that it is rare in the UAE population. CONCLUSION The present study represents the first STRC mutation reported in the UAE population. It also reinforces the power of next-generation sequencing in the diagnosis of heterogenous disorders such as nonsyndromic hearing loss.
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Affiliation(s)
- Mona Mahfood
- 1 Department of Applied Biology, College of Sciences, University of Sharjah, Sharjah, United Arab Emirates
| | | | - Abdullah Al Mutery
- 1 Department of Applied Biology, College of Sciences, University of Sharjah, Sharjah, United Arab Emirates.,2 Molecular Genetics Research Laboratory, University of Sharjah, Sharjah, United Arab Emirates
| | - Abdelaziz Tlili
- 1 Department of Applied Biology, College of Sciences, University of Sharjah, Sharjah, United Arab Emirates.,2 Molecular Genetics Research Laboratory, University of Sharjah, Sharjah, United Arab Emirates.,3 Human Genetics and Stem Cell Laboratory, Research Institute of Sciences and Engineering, University of Sharjah, Sharjah, United Arab Emirates
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18
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Abe S, Nishio S, Yokota Y, Moteki H, Kumakawa K, Usami S. Diagnostic pitfalls for GJB2-related hearing loss: A novel deletion detected by Array-CGH analysis in a Japanese patient with congenital profound hearing loss. Clin Case Rep 2018; 6:2111-2116. [PMID: 30455902 PMCID: PMC6230644 DOI: 10.1002/ccr3.1800] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 08/05/2018] [Accepted: 08/12/2018] [Indexed: 11/10/2022] Open
Abstract
Here, we report a novel deletion (copy number variation: CNV) in the GJB2 gene observed in a Japanese hearing loss patient. The deleted segment started in the middle of the GJB2 gene, but the GJB6 gene remained intact. This partial deletion in the GJB2 gene highlights the need for further improvements in GJB2 screening.
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Affiliation(s)
- Satoko Abe
- Department of OtorhinolaryngologyToranomon HospitalTokyoJapan
| | - Shin‐ya Nishio
- Department of OtolaryngologyShinshu University School of MedicineNaganoJapan
- Department of Hearing Implant SciencesShinshu University School of MedicineNaganoJapan
| | - Yoh Yokota
- Department of OtolaryngologyShinshu University School of MedicineNaganoJapan
| | - Hideaki Moteki
- Department of OtolaryngologyShinshu University School of MedicineNaganoJapan
- Department of Hearing Implant SciencesShinshu University School of MedicineNaganoJapan
| | - Kozo Kumakawa
- Department of OtorhinolaryngologyToranomon HospitalTokyoJapan
| | - Shin‐ichi Usami
- Department of OtolaryngologyShinshu University School of MedicineNaganoJapan
- Department of Hearing Implant SciencesShinshu University School of MedicineNaganoJapan
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19
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Jaiganesh A, Narui Y, Araya-Secchi R, Sotomayor M. Beyond Cell-Cell Adhesion: Sensational Cadherins for Hearing and Balance. Cold Spring Harb Perspect Biol 2018; 10:a029280. [PMID: 28847902 PMCID: PMC6008173 DOI: 10.1101/cshperspect.a029280] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Cadherins form a large family of proteins often involved in calcium-dependent cellular adhesion. Although classical members of the family can provide a physical bond between cells, a subset of special cadherins use their extracellular domains to interlink apical specializations of single epithelial sensory cells. Two of these cadherins, cadherin-23 (CDH23) and protocadherin-15 (PCDH15), form extracellular "tip link" filaments that connect apical bundles of stereocilia on hair cells essential for inner-ear mechanotransduction. As these bundles deflect in response to mechanical stimuli from sound or head movements, tip links gate hair-cell mechanosensitive channels to initiate sensory perception. Here, we review the unusual and diverse structural properties of these tip-link cadherins and the functional significance of their deafness-related missense mutations. Based on the structural features of CDH23 and PCDH15, we discuss the elasticity of tip links and models that bridge the gap between the nanomechanics of cadherins and the micromechanics of hair-cell bundles during inner-ear mechanotransduction.
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Affiliation(s)
- Avinash Jaiganesh
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210
| | - Yoshie Narui
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210
| | - Raul Araya-Secchi
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210
| | - Marcos Sotomayor
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210
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20
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Marková SP, Brožková DŠ, Laššuthová P, Mészárosová A, Krůtová M, Neupauerová J, Rašková D, Trková M, Staněk D, Seeman P. STRC Gene Mutations, Mainly Large Deletions, are a Very Important Cause of Early-Onset Hereditary Hearing Loss in the Czech Population. Genet Test Mol Biomarkers 2018; 22:127-134. [PMID: 29425068 DOI: 10.1089/gtmb.2017.0155] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
INTRODUCTION Hearing loss (HL) is the most common sensory deficit in humans. HL is an extremely heterogeneous condition presenting most frequently as a nonsyndromic (NS) condition inherited in an autosomal recessive (AR) pattern, termed DFNB. Mutations affecting the STRC gene cause DFNB type 16. Various types of mutations within the STRC gene have been reported from the U.S. and German populations, but no information about the relative contribution of STRC mutations to NSHL-AR among Czech patients is available. METHODS AND PATIENTS Two hundred and eighty-eight patients with prelingual NSHL, either sporadic (n = 207) or AR (n = 81), who had been previously tested negative for the mutations affecting the GJB2 gene, were included in the study. These patients were tested for STRC mutations by a quantitative comparative fluorescent polymerase chain reaction (QF-PCR) assay. In addition, 31 of the 81 NSHL-AR patients were analyzed by massively parallel sequencing using one of two different gene panels: 23 patients were analyzed by multiplex-ligation probe amplification (MLPA); and 9 patients by SNP microarrays. RESULTS Causal mutations affecting the STRC gene (including copy number variations [CNVs] and point mutations) were found in 5.5% of all patients and 13.6% of the 81 patients in the subgroup with NSHL-AR. CONCLUSION Our results provide strong evidence that STRC gene mutations are an important cause of NSHL-AR in Czech HL patients and are probably the second most common cause of DFNB. Large CNVs were more frequent than point mutations and it is reasonable to test them first by a QF-PCR method-a simple, accessible, and efficient tool for STRC CNV detection, which can be combined by MLPA.
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Affiliation(s)
- Simona Poisson Marková
- 1 DNA Laboratory, Department of Paediatric Neurology, 2nd Faculty of Medicine, Motol University Hospital, Charles University in Prague , Prague, Czech Republic
| | - Dana Šafka Brožková
- 1 DNA Laboratory, Department of Paediatric Neurology, 2nd Faculty of Medicine, Motol University Hospital, Charles University in Prague , Prague, Czech Republic
| | - Petra Laššuthová
- 1 DNA Laboratory, Department of Paediatric Neurology, 2nd Faculty of Medicine, Motol University Hospital, Charles University in Prague , Prague, Czech Republic
| | - Anna Mészárosová
- 1 DNA Laboratory, Department of Paediatric Neurology, 2nd Faculty of Medicine, Motol University Hospital, Charles University in Prague , Prague, Czech Republic
| | - Marcela Krůtová
- 1 DNA Laboratory, Department of Paediatric Neurology, 2nd Faculty of Medicine, Motol University Hospital, Charles University in Prague , Prague, Czech Republic
| | - Jana Neupauerová
- 1 DNA Laboratory, Department of Paediatric Neurology, 2nd Faculty of Medicine, Motol University Hospital, Charles University in Prague , Prague, Czech Republic
| | | | | | - David Staněk
- 1 DNA Laboratory, Department of Paediatric Neurology, 2nd Faculty of Medicine, Motol University Hospital, Charles University in Prague , Prague, Czech Republic
| | - Pavel Seeman
- 1 DNA Laboratory, Department of Paediatric Neurology, 2nd Faculty of Medicine, Motol University Hospital, Charles University in Prague , Prague, Czech Republic
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STRC Deletion is a Frequent Cause of Slight to Moderate Congenital Hearing Impairment in the Czech Republic. Otol Neurotol 2018; 38:e393-e400. [PMID: 28984810 DOI: 10.1097/mao.0000000000001571] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVE This study aimed to clarify the molecular epidemiology of hearing loss by identifying the responsible genes in patients without GJB2 mutations. STUDY DESIGN Prospective genetic study. SETTING Tertiary referral hospital. PATIENTS Fifty one patients with bilateral sensorineural hearing loss, 20 men, and 31 women, mean age 24.9 years, range 3 to 64 years, from 49 families. GJB2 and deltaGJB6-D13S1830 mutations were excluded previously. INTERVENTION Diagnostic. Sixty-nine genes reported to be causative of hearing loss were analyzed. Sequence capture technology, next-generation sequencing, and multiplex ligation-dependent probe amplification (MLPA) were used. Coverage of STRC was screened in Integrative Genomics Viewer software. MAIN OUTCOME MEASURE Identification of causal pathogenic mutations in genes related to deafness. RESULTS Five families (10%) had recessive STRC deletions or mutations. Five unrelated patients (10%) had recessive mutations in TMPRSS3, USH2A, PCDH15, LOXHD1, and MYO15A. Three families (6%) had autosomal dominant mutations in MYO6A, KCNQ4, and SIX1. One family (2%) had an X-linked POU3F4 mutation. Thus, we identified the cause of hearing loss in 28% of the families studied. CONCLUSIONS Following GJB2, STRC was the second most frequently mutated gene in patients from the Czech Republic with hearing loss. To decrease the cost of testing, we recommend STRC deletion screening with MLPA before next-generation sequencing. The existence of a pseudogene and polymorphic STRC regions can lead to false-positive or false-negative results when copy number variation analysis is based on next-generation sequencing data.
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Nishio S, Moteki H, Usami S. Simple and efficient germline copy number variant visualization method for the Ion AmpliSeq™ custom panel. Mol Genet Genomic Med 2018; 6:678-686. [PMID: 29633566 PMCID: PMC6081219 DOI: 10.1002/mgg3.399] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 03/02/2018] [Accepted: 03/06/2018] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Recent advances in molecular genetic analysis using next-generation sequencing (NGS) have drastically accelerated the identification of disease-causing gene mutations. Most next-generation sequencing analyses of inherited diseases have mainly focused on single-nucleotide variants and short indels, although, recently, structure variations including copy number variations have come to be considered an important cause of many different diseases. However, only a limited number of tools are available for multiplex PCR-based target genome enrichment. METHODS In this paper, we reported a simple and efficient copy number variation visualization method for Ion AmpliSeq™ target resequencing data. Unlike the hybridization capture-based target genome enrichment system, Ion AmpliSeq™ reads are multiplex PCR products, and each read generated by the same amplicon is quite uniform in length and position. Based on this feature, the depth of coverage information for each amplicon included in the barcode/amplicon coverage matrix file was used for copy number detection analysis. We also performed copy number analysis to investigate the utility of this method through the use of positive controls and a large Japanese hearing loss cohort. RESULTS Using this method, we successfully confirmed previously reported copy number loss cases involving the STRC gene and copy number gain in trisomy 21 cases. We also performed copy number analysis of a large Japanese hearing loss cohort (2,475 patients) and identified many gene copy number variants. The most prevalent copy number variation was STRC gene copy number loss, with 129 patients carrying this copy number variation. CONCLUSION Our copy number visualization method for Ion AmpliSeq™ data can be utilized in efficient copy number analysis for the comparison of a large number of samples. This method is simple and requires only easy calculations using standard spread sheet software.
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Affiliation(s)
- Shin‐ya Nishio
- Department of OtorhinolaryngologyShinshu University School of MedicineMatsumoto CityJapan
| | - Hideaki Moteki
- Department of OtorhinolaryngologyShinshu University School of MedicineMatsumoto CityJapan
| | - Shin‐ichi Usami
- Department of OtorhinolaryngologyShinshu University School of MedicineMatsumoto CityJapan
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23
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Chang MY, Lee C, Han JH, Kim MY, Park HR, Kim N, Park WY, Oh DY, Choi BY. Expansion of phenotypic spectrum of MYO15A pathogenic variants to include postlingual onset of progressive partial deafness. BMC MEDICAL GENETICS 2018; 19:29. [PMID: 29482514 PMCID: PMC6389081 DOI: 10.1186/s12881-018-0541-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 02/12/2018] [Indexed: 12/20/2022]
Abstract
BACKGROUND MYO15A variants, except those in the N-terminal domain, have been shown to be associated with congenital or pre-lingual severe-to-profound hearing loss (DFNB3), which ultimately requires cochlear implantation in early childhood. Recently, such variants have also been shown to possibly cause moderate-to-severe hearing loss. Herein, we also demonstrate that some MYO15A mutant alleles can cause postlingual onset of progressive partial deafness. METHODS Two multiplex Korean families (SB246 and SB224), manifesting postlingual, progressive, partial deafness in an autosomal recessive fashion, were recruited. Molecular genetics testing was performed in two different pipelines, in a parallel fashion, for the SB246 family: targeted exome sequencing (TES) of 129 known deafness genes from the proband and whole exome sequencing (WES) of all affected subjects. Only the former pipeline was performed for the SB224 family. Rigorous bioinformatics analyses encompassing structural variations were executed to investigate any causative variants. RESULTS In the SB246 family, two different molecular diagnostic pipelines provided exactly the same candidate variants: c.5504G > A (p.R1835H) in the motor domain and c.10245_10247delCTC (p.S3417del) in the FERM domain of MYO15A. In the SB224 family, c.9790C > T (p.Q3264X) and c.10263C > G (p.I3421M) in the FERM domain were detected as candidate variants. CONCLUSIONS Some recessive MYO15A variants can cause postlingual onset of progressive partial deafness. The phenotypic spectrum of DFNB3 should be extended to include such partial deafness. The mechanism for a milder phenotype could be due to the milder pathogenic potential from hypomorphic alleles of MYO15A or the presence of modifier genes. This merits further investigation.
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Affiliation(s)
- Mun Young Chang
- Department of Otorhinolaryngology-Head and Neck Surgery, Chung-Ang University College of Medicine, 102 Heukseok-ro, Dongjak-gu, 06973, Seoul, Republic of Korea
| | - Chung Lee
- Samsung Genome Institute, Samsung Medical Center, 81 Irwon-ro, Gangnam-gu, 06351, Seoul, Republic of Korea.,Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, 16419, Suwon, Republic of Korea
| | - Jin Hee Han
- Department of Otorhinolaryngology, Seoul National University Bundang Hospital, 82 Gumi-ro 173 beon-gil, Bundang-gu, 13620, Seongnam, 463-707, Republic of Korea
| | - Min Young Kim
- Department of Otorhinolaryngology, Seoul National University Bundang Hospital, 82 Gumi-ro 173 beon-gil, Bundang-gu, 13620, Seongnam, 463-707, Republic of Korea
| | - Hye-Rim Park
- Department of Otorhinolaryngology, Seoul National University Bundang Hospital, 82 Gumi-ro 173 beon-gil, Bundang-gu, 13620, Seongnam, 463-707, Republic of Korea
| | - Nayoung Kim
- Samsung Genome Institute, Samsung Medical Center, 81 Irwon-ro, Gangnam-gu, 06351, Seoul, Republic of Korea
| | - Woong-Yang Park
- Samsung Genome Institute, Samsung Medical Center, 81 Irwon-ro, Gangnam-gu, 06351, Seoul, Republic of Korea.,Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, 16419, Suwon, Republic of Korea.,Department of Molecular Cell Biology, School of Medicine, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, 16419, Suwon, Republic of Korea
| | - Doo Yi Oh
- Department of Otorhinolaryngology, Seoul National University Bundang Hospital, 82 Gumi-ro 173 beon-gil, Bundang-gu, 13620, Seongnam, 463-707, Republic of Korea
| | - Byung Yoon Choi
- Department of Otorhinolaryngology, Seoul National University Bundang Hospital, 82 Gumi-ro 173 beon-gil, Bundang-gu, 13620, Seongnam, 463-707, Republic of Korea. .,Wide River Institute of Immunology, Seoul National University College of Medicine, 101 Dabyeonbatgil, 25159, Hongcheon, Republic of Korea.
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24
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Fritzsch B, Elliott KL. Gene, cell, and organ multiplication drives inner ear evolution. Dev Biol 2017; 431:3-15. [PMID: 28866362 DOI: 10.1016/j.ydbio.2017.08.034] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 04/27/2017] [Accepted: 08/25/2017] [Indexed: 12/14/2022]
Abstract
We review the development and evolution of the ear neurosensory cells, the aggregation of neurosensory cells into an otic placode, the evolution of novel neurosensory structures dedicated to hearing and the evolution of novel nuclei in the brain and their input dedicated to processing those novel auditory stimuli. The evolution of the apparently novel auditory system lies in duplication and diversification of cell fate transcription regulation that allows variation at the cellular level [transforming a single neurosensory cell into a sensory cell connected to its targets by a sensory neuron as well as diversifying hair cells], organ level [duplication of organ development followed by diversification and novel stimulus acquisition] and brain nuclear level [multiplication of transcription factors to regulate various neuron and neuron aggregate fate to transform the spinal cord into the unique hindbrain organization]. Tying cell fate changes driven by bHLH and other transcription factors into cell and organ changes is at the moment tentative as not all relevant factors are known and their gene regulatory network is only rudimentary understood. Future research can use the blueprint proposed here to provide both the deeper molecular evolutionary understanding as well as a more detailed appreciation of developmental networks. This understanding can reveal how an auditory system evolved through transformation of existing cell fate determining networks and thus how neurosensory evolution occurred through molecular changes affecting cell fate decision processes. Appreciating the evolutionary cascade of developmental program changes could allow identifying essential steps needed to restore cells and organs in the future.
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Affiliation(s)
- Bernd Fritzsch
- University of Iowa, Department of Biology, Iowa City, IA 52242, United States.
| | - Karen L Elliott
- University of Iowa, Department of Biology, Iowa City, IA 52242, United States
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