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Caroça C, de Matos TM, Ribeiro D, Lourenço V, Martins T, Campelo P, Fialho G, Silva SN, Paço J, Caria H. Genetic Basis of Nonsyndromic Sensorineural Hearing Loss in the Sub-Saharan African Island Population of São Tomé and Príncipe: The Role of the DFNB1 Locus? OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2018; 20:449-55. [PMID: 27501294 DOI: 10.1089/omi.2016.0067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Hearing loss (HL) is a common condition with both genetic and environmental causes, and it greatly impacts global health. The prevalence of HL is reportedly higher in developing countries such as the Sub-Saharan African island of São Tomé and Príncipe, where the deaf community is estimated to be less than 1% of the population. We investigated the role of the DFNB1 locus (GJB2 and GJB6 genes) in the etiology of nonsyndromic sensorineural hearing loss (NSSHL) in São Tomé and Príncipe. A sample of 316 individuals, comprising 136 NSSHL patients (92 bilateral, 44 unilateral) and 180 controls, underwent a clinical and audiological examination. Sequencing of the GJB2 coding region and testing for the (GJB6-D13S1830) and del(GJB6-D13S1854) GJB6 deletions were performed. A total of 311 out of 316 individuals were successfully analyzed regarding the GJB2 and GJB6 genetic variations, respectively. The frequency of the GJB2 coding mutations in patients and controls was low. Some of those coding mutations are the most commonly found in Eurasian and Mediterranean populations and have also been identified in Portugal. None of the GJB6 deletions was present. The presence of certain coding variants in São Tomé and Príncipe suggests a non-Sub-Saharan genetic influx and supports the previously reported genetic influx from European (mainly Portuguese) ancestors. In summary, DFNB1 locus does not appear to be a major contributor to NSSHL in São Tomé and Príncipe. However, the presence of both pathogenic and likely pathogenic mutations in GJB2 suggests that GJB2-related NSSHL might still occur in this population, warranting further research on GJB2 testing in NSSHL cases.
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Affiliation(s)
- Cristina Caroça
- 1 Otolaryngology Department, Nova Medical School/Faculty of Medical Sciences , Universidade Nova de Lisboa, Lisboa, Portugal .,2 Hospital CUF Infante Santo , Otolaryngology Department, Hospital CUF Infante Santo, Lisboa, Portugal
| | - Tiago Morim de Matos
- 3 Deafness Research Group, Biomedicine and Translational Research, BioISI, Faculty of Sciences, University of Lisbon , Lisbon, Portugal
| | - Diogo Ribeiro
- 2 Hospital CUF Infante Santo , Otolaryngology Department, Hospital CUF Infante Santo, Lisboa, Portugal
| | - Vera Lourenço
- 2 Hospital CUF Infante Santo , Otolaryngology Department, Hospital CUF Infante Santo, Lisboa, Portugal
| | - Tânia Martins
- 2 Hospital CUF Infante Santo , Otolaryngology Department, Hospital CUF Infante Santo, Lisboa, Portugal
| | - Paula Campelo
- 2 Hospital CUF Infante Santo , Otolaryngology Department, Hospital CUF Infante Santo, Lisboa, Portugal
| | - Graça Fialho
- 3 Deafness Research Group, Biomedicine and Translational Research, BioISI, Faculty of Sciences, University of Lisbon , Lisbon, Portugal
| | - Susana Nunes Silva
- 4 Centre for Toxicogenomics and Human Health (ToxOmics), NOVA Medical School , Faculty of Medical Sciences, Universidade Nova de Lisboa, Lisboa, Portugal
| | - João Paço
- 1 Otolaryngology Department, Nova Medical School/Faculty of Medical Sciences , Universidade Nova de Lisboa, Lisboa, Portugal .,2 Hospital CUF Infante Santo , Otolaryngology Department, Hospital CUF Infante Santo, Lisboa, Portugal
| | - Helena Caria
- 3 Deafness Research Group, Biomedicine and Translational Research, BioISI, Faculty of Sciences, University of Lisbon , Lisbon, Portugal .,5 School of Health, Polytechnic Institute of Setubal , Setubal, Portugal
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Laleh MA, Naseri M, Zonouzi AAP, Zonouzi AP, Masoudi M, Ahangari N, Shams L, Nejatizadeh A. Diverse pattern of gap junction beta-2 and gap junction beta-4 genes mutations and lack of contribution of DFNB21, DFNB24, DFNB29, and DFNB42 loci in autosomal recessive nonsyndromic hearing loss patients in Hormozgan, Iran. JOURNAL OF RESEARCH IN MEDICAL SCIENCES 2017; 22:99. [PMID: 28900455 PMCID: PMC5583625 DOI: 10.4103/jrms.jrms_976_16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 04/26/2017] [Accepted: 05/12/2017] [Indexed: 11/04/2022]
Abstract
BACKGROUND We aimed to determine the contribution of four DFNB loci and mutation analysis of gap junction beta-2 (GJB2) and GJB4 genes in autosomal recessive nonsyndromic hearing loss (ARNSHL) in South of Iran. MATERIALS AND METHODS A total of 36 large ARNSHL pedigrees with at least two affected subjects were enrolled in the current study. The GJB2 and GJB4 genes mutations were screened using direct sequencing method. The GJB2 and GJB4 negative families were analyzed for the linkage to DFNB21, DFNB24, DFNB29, and DFNB42 loci by genotyping the corresponding STR markers using polymerase chain reaction-PAGE method. RESULTS We found a homozygous nonsense mutation W77X and a homozygous missense mutation C169W in 5.55% of studied families in GJB2 and GJB4 genes, respectively. Five heterozygous mutations including V63G, A78T, and R127H in GJB2 gene, and R103C and R227W in GJB4 gene were detected. We identified two novel variations V63G in GJB2 and R227W in GJB4. In silico analysis predicted that both novel variations are deleterious mutations. We did not unveil any linkage between DFNB21, DFNB24, DFNB29, and DFNB42 loci and ARNSHL among studied families. CONCLUSION This is the first report of GJB2 and GJB4 mutations from Hormozgan population. According to the previous publications regarding GJB2 and GJB4 mutations, the distribution of the mutations is different from other parts of Iran that should be considered in primary health-care programs. Further investigations are needed to evaluate the contribution of other loci in ARNSHL subjects in South of Iran.
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Affiliation(s)
- Masoud Akbarzadeh Laleh
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Marzieh Naseri
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | | | | | - Marjan Masoudi
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Najmeh Ahangari
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Leila Shams
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Azim Nejatizadeh
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
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The controversial p.Met34Thr variant in GJB2 gene: Two siblings, one genotype, two phenotypes. Int J Pediatr Otorhinolaryngol 2015; 79:1316-9. [PMID: 26117665 DOI: 10.1016/j.ijporl.2015.05.041] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 05/27/2015] [Accepted: 05/31/2015] [Indexed: 01/02/2023]
Abstract
INTRODUCTION Recent advances in molecular genetics have increased the identification of genes and mutations responsible for inherited forms of hearing loss (HL), enabling early detection of these cases. Approximately, 60% of early-onset HL cases are due to genetic causes, of which 70% are non-syndromic. Of these, 75-80% are inherited in an autosomal recessive pattern (DFNB). Mutations in GJB2 gene, coding for connexin 26 (Cx26), are the major cause of autosomal recessive hereditary HL, but some GJB2 mutations are yet of unclear or controversial significance. OBJECTIVES The aim of the present study was to identify the etiology of hearing loss, and correlate genotype-phenotype, in two Portuguese siblings with profound and moderate non-syndromic sensorineural bilateral HL. MATERIAL AND METHODS The affected subjects and their parents underwent audiological and genetic study. Molecular analysis of GJB2 gene was performed, searching for mutations in the coding region and receptor splicing site by automated sequencing. RESULTS The onset and the degree of HL were different in the two affected subjects. However, the same GJB2 genotype [p.Met34Thr]+[p.Arg184Pro] was identified in both siblings. The c.551G>C (p.Arg184Pro) and c.101T>C (p.Met34Thr) missense variants were inherited from the father and mother, respectively, both heterozygous carriers of these variants. CONCLUSION The clinical and genetic data here presented suggest that the non-syndromic sensorineural HL of these two Portuguese siblings might be due to the presence of p.Met34Thr and p.Arg184Pro variants in compound heterozygosity. If so, p.Met34Thr variant could have function as a hypomorphic allele that may cause HL depending on the opposing GJB2 allele. The observed phenotypic variability may not, however, be solely explained by variable expression of this genotype. A putative modifier gene or mutations in another HL-associated gene could probably be contributing to the severe HL in one of the siblings.
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Frequency of GJB2 and del(GJB6-D13S1830) mutations among an Ecuadorian mestizo population. Int J Pediatr Otorhinolaryngol 2014; 78:1648-54. [PMID: 25085072 DOI: 10.1016/j.ijporl.2014.07.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 07/08/2014] [Accepted: 07/12/2014] [Indexed: 12/11/2022]
Abstract
OBJECTIVE The frequency of GJB2 mutations and of the del(GJB6-D13S1830) mutation has not been established among the Ecuadorian mestizo population diagnosed with autosomal recessive non-syndromic hearing loss. A genetic analysis was therefore designed in order to do so. METHODS The sample population included 111 subjects of which 26 were autosomal recessive non-syndromic hearing loss probands. Posterior to PCR amplification, sequencing analysis of exon 2 was used for mutational detection of the GJB2 gene; a multiplex PCR method was used for detection of the del(GJB6-D13S1830) mutation. The ratio of subjects with a certain state of the mutation (heterozygous/homozygous) is expressed as a percentage and significant differences between probands and controls were calculated using Fisher's exact test; P<0.05 was considered significant. RESULTS A total of 104 mutations belonging to 8 allelic variations were identified. The most common being the V27I (58.9%); however, as this variation is a non-pathogenic polymorphism, Q7X, with a total of 19 mutated alleles, was the most frequent mutation (18.3%). The V27I polymorphism was the only variation distributed homogenously among probands and controls (P=0.351). Based on physical analyses of multiple patients we confirm that Q7X causes a non-syndromic form of hearing loss and propose that it is a possible predominant mutation in the Ecuadorian population. CONCLUSIONS This is the first study of its kind among the Ecuadorian population and a preliminary step in establishing GJB2 and del(GJB6-D13S1830) mutational frequencies in this population; it is also the first to report of such a high frequency of the Q7X mutation. The data presented here brings Ecuador a step closer to providing more efficient treatment for a broader number of patients; additionally, it contributes to a better understanding of the relationship between autosomal recessive non-syndromic hearing loss and mutations on the GJB2 gene.
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Shafique S, Siddiqi S, Schraders M, Oostrik J, Ayub H, Bilal A, Ajmal M, Seco CZ, Strom TM, Mansoor A, Mazhar K, Shah STA, Hussain A, Azam M, Kremer H, Qamar R. Genetic spectrum of autosomal recessive non-syndromic hearing loss in Pakistani families. PLoS One 2014; 9:e100146. [PMID: 24949729 PMCID: PMC4065008 DOI: 10.1371/journal.pone.0100146] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2014] [Accepted: 05/22/2014] [Indexed: 12/01/2022] Open
Abstract
The frequency of inherited bilateral autosomal recessive non-syndromic hearing loss (ARNSHL) in Pakistan is 1.6/1000 individuals. More than 50% of the families carry mutations in GJB2 while mutations in MYO15A account for about 5% of recessive deafness. In the present study a cohort of 30 ARNSHL families was initially screened for mutations in GJB2 and MYO15A. Homozygosity mapping was performed by employing whole genome single nucleotide polymorphism (SNP) genotyping in the families that did not carry mutations in GJB2 or MYO15A. Mutation analysis was performed for the known ARNSHL genes present in the homozygous regions to determine the causative mutations. This allowed the identification of a causative mutation in all the 30 families including 9 novel mutations, which were identified in 9 different families (GJB2 (c.598G>A, p.Gly200Arg); MYO15A (c.9948G>A, p.Gln3316Gln; c.3866+1G>A; c.8767C>T, p.Arg2923* and c.8222T>C, p.Phe2741Ser), TMC1 (c.362+18A>G), BSND (c.97G>C, p.Val33Leu), TMPRSS3 (c.726C>G, p.Cys242Trp) and MSRB3 (c.20T>G, p.Leu7Arg)). Furthermore, 12 recurrent mutations were detected in 21 other families. The 21 identified mutations included 10 (48%) missense changes, 4 (19%) nonsense mutations, 3 (14%) intronic mutations, 2 (9%) splice site mutations and 2 (9%) frameshift mutations. GJB2 accounted for 53% of the families, while mutations in MYO15A were the second most frequent (13%) cause of ARNSHL in these 30 families. The identification of novel as well as recurrent mutations in the present study increases the spectrum of mutations in known deafness genes which could lead to the identification of novel founder mutations and population specific mutated deafness genes causative of ARNSHL. These results provide detailed genetic information that has potential diagnostic implication in the establishment of cost-efficient allele-specific analysis of frequently occurring variants in combination with other reported mutations in Pakistani populations.
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Affiliation(s)
- Sobia Shafique
- COMSATS Institute of Information Technology, Park Road, Islamabad, Pakistan
| | - Saima Siddiqi
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
| | - Margit Schraders
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, Nijmegen, The Netherlands
- Nijmegen Centre for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Jaap Oostrik
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, Nijmegen, The Netherlands
- Nijmegen Centre for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Humaira Ayub
- COMSATS Institute of Information Technology, Park Road, Islamabad, Pakistan
| | - Ammad Bilal
- Simon Fraser University, Vancouver, British Colombia, Canada
| | - Muhammad Ajmal
- COMSATS Institute of Information Technology, Park Road, Islamabad, Pakistan
| | - Celia Zazo Seco
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, Nijmegen, The Netherlands
- Nijmegen Centre for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Tim M. Strom
- Institute of Human Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Atika Mansoor
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
| | - Kehkashan Mazhar
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
| | - Syed Tahir A. Shah
- COMSATS Institute of Information Technology, Park Road, Islamabad, Pakistan
| | - Alamdar Hussain
- COMSATS Institute of Information Technology, Park Road, Islamabad, Pakistan
| | - Maleeha Azam
- COMSATS Institute of Information Technology, Park Road, Islamabad, Pakistan
| | - Hannie Kremer
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, Nijmegen, The Netherlands
- Nijmegen Centre for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands
- * E-mail: (HK); (RQ)
| | - Raheel Qamar
- COMSATS Institute of Information Technology, Park Road, Islamabad, Pakistan
- Al-Nafees Medical College & Hospital, Isra University, Islamabad, Pakistan
- * E-mail: (HK); (RQ)
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Gonçalves A, Matos T, Simões-Teixeira H, Pimenta Machado M, Simão M, Dias Ó, Andrea M, Fialho G, Caria H. WFS1 and non-syndromic low-frequency sensorineural hearing loss: A novel mutation in a Portuguese case. Gene 2014; 538:288-91. [DOI: 10.1016/j.gene.2014.01.040] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 01/02/2014] [Accepted: 01/13/2014] [Indexed: 11/17/2022]
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Matos TD, Simões-Teixeira H, Caria H, Gonçalves AC, Chora J, Correia MDC, Moura C, Rosa H, Monteiro L, O'Neill A, Dias Ó, Andrea M, Fialho G. Spectrum and frequency of GJB2 mutations in a cohort of 264 Portuguese nonsyndromic sensorineural hearing loss patients. Int J Audiol 2013; 52:466-71. [PMID: 23668481 DOI: 10.3109/14992027.2013.783719] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To assess the spectrum and prevalence of mutations in the GJB2 gene in Portuguese nonsyndromic sensorineural hearing loss (NSSHL) patients. DESIGN Sequencing of the coding region, basal promoter, exon 1, and donor splice site of the GJB2 gene; screening for the presence of the two common GJB6 deletions. STUDY SAMPLE A cohort of 264 Portuguese NSSHL patients. RESULTS At least one out of 21 different GJB2 variants was identified in 80 (30.2%) of the 264 patients analysed. Two mutant alleles were found in 53 (20%) of these probands, of which 83% (44/53) harboured at least one c.35delG allele. Twenty-seven (10.2%) of the probands harboured only one mutant allele. Subsequent analysis revealed that the GJB6 deletion del(GJB6-D13S1854) was present in at least 7.4% (2/27) of the patients carrying only one mutant GJB2 allele. Overall, one in five (55/264) of the patients were diagnosed as having DFNB1-related NSSHL, of which the vast majority (53/55) harboured only GJB2 mutations. CONCLUSIONS This study provides clear demonstration that mutations in the GJB2 gene are an important cause of NSSHL in Portugal, thus representing a valuable indicator as regards therapeutical and rehabilitation options, as well as genetic counseling of these patients and their families.
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Affiliation(s)
- Tiago Daniel Matos
- Centre for Biodiversity, Functional, and Integrative Genomics BioFIG, Faculty of Science, University of Lisbon, Lisboa, Portugal
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Gonçalves AC, Chora J, Matos TD, Santos R, O'Neill A, Escada P, Fialho G, Caria H. A novel p.Leu213X mutation in GJB2 gene in a Portuguese family. Int J Pediatr Otorhinolaryngol 2013; 77:89-91. [PMID: 23141775 DOI: 10.1016/j.ijporl.2012.10.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 10/04/2012] [Accepted: 10/06/2012] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Hearing loss is the most common sensory disability and is present in about 1.9 per 1000 infants at birth. The DFNB1 locus (13q11-q12) includes the genes GJB2, coding for connexin 26, and GJB6, encoding connexin 30. More than 100 mutations have been identified associated with autosomal dominant and recessive hearing loss in the GJB2 gene. OBJECTIVES The aim of the present study was to identify the genetic aetiology of deafness in two Portuguese individuals, presenting nonsyndromic sensorineural moderate and severe hearing loss, respectively. PATIENTS AND METHODS The individuals were evaluated in both ears by pure tone audiometry and blood samples were collected after written informed consent was signed. DNA extraction and PCR amplification of GJB2 coding region followed standard methodologies. PCR products were automatically sequenced in both directions. RESULTS We identified a novel mutation, c.638T>A (p.Leu213X), in GJB2 gene. This nonsense mutation was found in both siblings, and was inherited from their hearing father. Molecular analysis showed that the two siblings were also heterozygous for c.333-334delAA, a previously described GJB2 deletion. This novel mutation was not found in a random control sample of 480 individuals that were screened for coding region of GJB2 gene. p.Leu213X mutation identified in this study for the first time changes the codon 213, coding for a highly conserved and slowly evolving residue of connexin 26, localised to the C-terminus domain of the protein, to a STOP codon, leading to the deletion of the last 14 amino acids of the protein. CONCLUSION We can conclude that the aetiology of deafness in these individuals is due to the GJB2 genotype involving the c.333-334delAA deletion and the novel p.Leu213X mutation in compound heterozygosity.
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Affiliation(s)
- Ana Cláudia Gonçalves
- BioFIG, Center for Biodiversity, Functional and Integrative Genomics, Faculty of Science of the University of Lisbon, Portugal
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Novel connexin 30 and connexin 26 mutational spectrum in patients with progressive sensorineural hearing loss. The Journal of Laryngology & Otology 2012; 126:763-9. [DOI: 10.1017/s0022215112001119] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
AbstractObjective:Mutations in the gap junction protein beta-2 gene (‘GJB2’) are known to be responsible for mild to profound congenital and late-onset hearing loss. This study aimed to investigate the molecular basis of progressive hearing loss compared with non-progressive hearing loss.Methods:Following clinical otorhinolaryngological evaluation, a genetic analysis was performed in a cohort of 72 patients with progressive sensorineural hearing loss.Results:Pathological genotypes were established in 16 patients (22.2 per cent). Six different gap junction protein beta-2 gene mutations were detected in 15 patients, with the c.35delG mutation responsible for 56 per cent of the mutated alleles. A novel gap junction protein beta-6 gene (‘GJB6’) mutation (p.Met203Val) was observed in one patient with mild progressive hearing loss.Conclusion:Analyses of gap junction protein beta-2 and -6 genes revealed that similar pathological genotypes, occurring with similar frequencies, were responsible for progressive hearing loss, compared with reported genotypes for non-progressive hearing loss patients. Thus, genotype cannot be used to differentiate non-progressive from progressive hearing loss cases; in this study, patients both with and without an established pathological genotype had a similar clinical course.
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Abstracts. Int J Audiol 2011. [DOI: 10.3109/14992027.2011.588967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Simões-Teixeira H, Matos TD, Marques MC, Dias Ó, Andrea M, Barreiros E, Barreiros L, Moreno F, Fialho G, Caria H, del Castillo I. Novel splice-site mutation c.1615-2A>G (IVS14-2A>G) in the SLC26A4 gene causing Pendred syndrome in a consanguineous Portuguese family. Am J Med Genet A 2011; 155A:924-7. [DOI: 10.1002/ajmg.a.33740] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Accepted: 09/12/2010] [Indexed: 11/09/2022]
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