Waardenburg Syndrome Research Articles

SOX10 mutation causes Waardenburg syndrome associated with distinctive phenotypic features in an Iranian family: A clue for phenotype-directed genetic analysis

BackgroundWaardenburg syndrome (WS) is a neurocristopathy characterized by hearing impairment and pigmentary disturbances in hair, eyes, and skin. WS is clinically heterogeneous and can be subdivided into four major types (WS1–WS4) where WS4 or Shah–Waardenburg is diagnosed when WS2 is accompanied by Hirschsprung disease (HD). Mutations of SOX10, EDN3/EDNRB have been identified in association with WS4. This study was aimed to determine the pathogenic variant in an Iranian pedigree affected with WS4. MethodA two-generation pedigree with three affected members and considerable phenotypic heterogeneity was recruited. The proband was a 15-year-old boy, with severe to profound sensorineural hearing impairment, heterochromia iridis, hypoplastic blue eyes and Hirschprung disease. The other two also presented characteristics of WS2 and complained of chronic constipation with normal anorectal reflex. Sequencing of all exons and exon-intron boundaries of SOX10, EDN3/EDNRB revealed a heterozygous variant c.422T > C in exon 3 of SOX10 confirmed by a series of evidence to be pathogenic. It resulted in p.L141P at the protein level. Leucin 141 is located in Nuclear Export signal, HMG box of the protein. ConclusionThis study is the first report of a WS4 family in the Iranian population. The mutation is associated with distinctive phenotypic profile (association of anosmia and chronic constipation with SOX10 mutations) and could further improve diagnosis and counseling of WS in the Iranian population and can contribute to phenotype-directed genetic analysis.

EDNRB mutations cause Waardenburg syndrome type II in the heterozygous state.

Waardenburg syndrome (WS) is a genetic disorder characterized by sensorineural hearing loss and pigmentation anomalies. The clinical definition of four WS types is based on additional features due to defects in structures mostly arising from the neural crest, with type I and type II being the most frequent. While type I is tightly associated to PAX3 mutations, WS type II (WS2) remains partly enigmatic with mutations in known genes (MITF, SOX10) accounting for only 30% of the cases. We performed exome sequencing in a WS2 index case and identified a heterozygous missense variation in EDNRB. Interestingly, homozygous (and very rare heterozygous) EDNRB mutations are already described in type IV WS (i.e., in association with Hirschsprung disease [HD]) and heterozygous mutations in isolated HD. Screening of a WS2 cohort led to the identification of an overall of six heterozygous EDNRB variations. Clinical phenotypes, pedigrees and molecular segregation investigations unraveled a dominant mode of inheritance with incomplete penetrance. In parallel, cellular and functional studies showed that each of the mutations impairs the subcellular localization of the receptor or induces a defective downstream signaling pathway. Based on our results, we now estimate EDNRB mutations to be responsible for 5%-6% of WS2.

Analogs of human genetic skin disease in domesticated animals.

Genetic skin diseases encompass a vast, complex, and ever expanding field. Recognition of the features of these diseases is important to ascertain a correct diagnosis, initiate treatment, consider genetic counseling, and refer patients to specialists when the disease may impact other areas. Because genodermatoses may present with a vast array of features, it can be bewildering to memorize them. This manuscript will explain and depict some genetic skin diseases that occur in both humans and domestic animals and offer a connection and memorization aid for physicians. In addition, we will explore how animal diseases serve as a model to uncover the mechanisms of human disease.The genetic skin diseases we will review are pigmentary mosaicism, piebaldism, albinism, Griscelli syndrome, ectodermal dysplasias, Waardenburg syndrome, and mucinosis in both humans and domesticated animals.

A Scoring System to Predict the Severity of Hirschsprung Disease at Diagnosis and Its Correlation With Molecular Genetics.

Objectives Hirschsprung disease (HSCR) has a wide range of severity. There are nonsevere forms treated conservatively until surgery and severe forms that require an early stoma and prolonged hospitalization. Our objective was to establish a clinical scoring system to predict the severity of HSCR and to evaluate the possible existence of a clinical-genetic correlation. Methods We carried out a retrospective observational study including all HSCR cases treated in our hospital. The sample was divided into severe and nonsevere disease according to the number of surgical procedures, hospitalization time, and episodes of enterocolitis. The proposed score was applied at diagnosis, and the sensitivity, specificity, and optimal cut-point were determined. We conducted a prospective molecular study of RET, EDNRB, and EDN3 on all patients, as well as SOX10 in Waardenburg Syndrome type 4 forms. Results Among the 42 patients treated between 1983 and 2013, 15 met the severe disease criteria. This group had a higher mean score (13.15 ± 2.36) than the nonsevere group (8.15 ± 2.13; p < 0.001). A score ≥11 had a sensitivity of 87% and a specificity of 81% in detecting the severe cases. Causative mutations were identified in 12 patients, 8 of them in the severe group ( p = 0.015). Most of these mutations (75%) were located in the RET proto-oncogene. Conclusion The proposed scoring system enables the early selection of patients with severe behavior of HSCR. A value ≥11 showed good sensitivity and specificity for this purpose. Causative mutations were identified in more than 50% of patients who met the criteria for severe disease.

A de novo deletion mutation in SOX10 in a Chinese family with Waardenburg syndrome type 4

Waardenburg syndrome type 4 (WS4) or Waardenburg-Shah syndrome is a rare genetic disorder with a prevalence of <1/1,000,000 and characterized by the association of congenital sensorineural hearing loss, pigmentary abnormalities, and intestinal aganglionosis. There are three types of WS4 (WS4A–C) caused by mutations in endothelin receptor type B, endothelin 3, and SRY-box 10 (SOX10), respectively. This study investigated a genetic mutation in a Chinese family with one WS4 patient in order to improve genetic counselling. Genomic DNA was extracted, and mutation analysis of the three WS4 related genes was performed using Sanger sequencing. We detected a de novo heterozygous deletion mutation [c.1333delT (p.Ser445Glnfs*57)] in SOX10 in the patient; however, this mutation was absent in the unaffected parents and 40 ethnicity matched healthy controls. Subsequent phylogenetic analysis and three-dimensional modelling of the SOX10 protein confirmed that the c.1333delT heterozygous mutation was pathogenic, indicating that this mutation might constitute a candidate disease-causing mutation.

A new missense mutation in the paired domain of the mouse Pax3 gene.

Mice with dominant white spotting occurred spontaneously in the C3.NSY-(D11Mit74-D11Mit229) strain. Linkage analysis indicated that the locus for white spotting was located in the vicinity of the Pax3 gene on chromosome 1. Crosses of white-spotted mice showed that homozygosity for the mutation caused tail and limb abnormalities and embryonic lethality as a result of exencephaly; these phenotypes were analogous to those found in other Pax3 mutants. Sequence analysis identified a missense point mutation (c.101G>A) in exon 2 of Pax3 that resulted in a methionine to isoleucine conversion at amino acid 62 of the PAX3 protein. This mutation site was located in the N-terminal HTH (helix-turn-helix) motif of the paired domain of Pax3, which is necessary for binding to DNA and is highly conserved in vertebrate species. Alteration of DNA binding affinity was responsible for embryonic lethality in homozygotes and white spotting in heterozygotes. We named the mutant allele as Pax3Sp-Nag. The C3H/HeN-Pax3Sp-Nag strain may be useful for analyzing the function of Pax3 as a new model of the human disease, Waardenburg Syndrome.

A spontaneous and novel Pax3 mutant mouse that models Waardenburg syndrome and neural tube defects

BackgroundGenes responsible for reduced pigmentation phenotypes in rodents are associated with human developmental defects, such as Waardenburg syndrome, where patients display congenital deafness along with various abnormalities mostly related to neural crest development deficiency. ObjectiveIn this study, we identified a spontaneous mutant mouse line Rwa, which displays variable white spots on mouse bellies and white digits and tail, on a C57BL/6N genetic background. Curly tail and spina bifida were also observed, although at a lower penetrance. These phenotypes were dominantly inherited by offspring. We searched for the genetic mechanism of the observed phenotypes. MethodsWe harnessed a rapid mouse gene mapping system newly developed in our laboratories to identify a responsible gene. ResultsWe detected a region within chromosome 1 as a probable locus for the causal mutation. Dense mapping using interval markers narrowed the locus down to a 670-kbp region, containing four genes including Pax3, a gene known to be implicated in the types I and III Waardenburg syndrome. Extensive mutation screening of Pax3 detected an 841-bp deletion, spanning the promoter region and intron 1 of the gene. The defective allele of Pax3, named Pax3Rwa, lacked the first coding exon and co-segregated perfectly with the phenotypes, confirming its causal nature. The genetic background of Rwa mice is almost identical to that of inbred C57BL/6N. ConclusionThese results highlight Pax3Rwa mice as a beneficial tool for analyzing biological processes involving Pax3, in particular the development and migration of neural crest cells and melanocytes.

PAX3 gene mutation analysis for two Waardenburg syndrome type Ⅰ families and their prenatal diagnosis

Objective: To analyze the mutations of PAX3 gene in two Waardenburg syndrome type Ⅰ (WS1) pedigrees and make prenatal diagnosis for the high-risk 18-week-old fetus. Methods:PAX3 gene was first analyzed by Sanger sequencing and multiplex ligation-dependent probe amplification(MLPA) for detecting pathogenic mutation of the probands of the two pedigrees. The mutations were confirmed by MLPA and Sanger in parents and unrelated healthy individuals.Prenatal genetic diagnosis for the high-risk fetus was performed by amniotic fluid cell after genotyping. Results: A heterozygous PAX3 gene gross deletion (E7 deletion) was identified in all patients from WS1-01 family, and not found in 20 healthy individuals.Prenatal diagnosis in WS1-01 family indicated that the fetus was normal. Molecular studies identified a novel deletion mutation c. 1385_1386delCT within the PAX3 gene in all affected WS1-02 family members, but in none of the unaffected relatives and 200 healthy individuals. Conclusions:PAX3 gene mutation is etiological for two WS1 families. Sanger sequencing plus MLPA is effective and accurate for making gene diagnosis and prenatal diagnosis.

Clinical and genetic investigation of families with Waardenburg syndrome type 2

Objective:To investigate the clinical chacteration and molecular pathology of Waardenburg syndrome type 2 in seven families, and provide genetic diagnosis and hereditary counseling for family members. Method:Clinical data of seven families with WS2（14 patients）were collected. Peripheral blood samples of the probands and related family members were collected and genomic DNA was extracted. The coding sequences of microphthalmia associated transcription factor (MITF), sex-determining region Y-box 10(SOX10), snail family zinc finger 2 (SNAI2) and endothelin receptor type B（EDNRB）were analyzed by polymerase chain reaction and DNA sequencing. Then the raw data was analyzed. Result:The most common manifestations of WS2 are sensorineural hearing loss(10/14,71.4%), freckle(7/14, 50.0%)，heterochromia iridis(6/14, 42.9%) and premature greying(5/14,35.7%). All the deafness phenotype is congenital, bilateral profound sensorineural hearing loss. Freckles phenotype is different from cutaneous pigment abnormalities of WS in Westerners. The heterozygous mutation, c.328C>T in exon 3 of the MITF gene was detected in the proband and all patients of pedigree 2. However, no pathological mutation of the relevant genes (SOX10,SNAI2 and EDNRB) was detected in other pedigrees. Conclusion:There are obvious variations in clinical features of WS, while freckles may be a special subtype of cutaneous pigment disturbances. The MITF gene mutation, R110X,is therefore considered the disease causing mutation in pedigree WS02.However, there are novel disease causing genes or copy number variations in Waardenburg syndrome type 2, which require further research.

SOX10 mutation is relevant to inner ear malformation in patients with Waardenburg syndrome

Objective: To determine the relevance between the SOX10 mutation and Waardenburg syndrome (WS) accompanied with inner ear abnormality by analyzing the inner ear imaging results and molecular and genetic results of the WS patients with the SOX10 mutation. Methods: This study included 36 WS in patients during 2001 and 2015 in the department of otorhinolaryngology head and neck surgery, Chinese Peoples's Liberation Army General Hospital. The condition of the inner ear of each patient was assessed by analyzing HRCT scans of the temporal bone and MRI scans of the brain and internal auditory canal. Meanwhile, the possible pathogenic genes of WS, including SOX10, MITF, and PAX3, were also screened. Patients were divided into two groups according to SOX10 mutation.The Fisher accuracy test was used to determine statistical difference of inner ear deformation incidence between the two groups. Results: Among all 36 patients, 12 were found to have inner ear abnormality. Most abnormalities were posterior semicircular canal deformations, some accompanied with cochlear deformation and an enlarged vestibule. Among all patients, 9 patients were SOX10 heterozygous mutation carriers, among which six showed bilateral inner ear abnormality. Fisher accuracy test results suggested a significant correlation between the SOX10 mutation and inner ear abnormality in WS patients (P=0.036). Conclusion: This study found that WS patients with the SOX10 mutation are more likely to have deformed inner ears when compared to WS patients without the SOX10 mutation.

Molecular etiology and genotype-phenotype correlation of Chinese Han deaf patients with type I and type II Waardenburg Syndrome

Waardenburg syndrome (WS) characterized by sensorineural hearing loss and pigmentary abnormalities is genetically heterogeneous and phenotypically variable. This study investigated the molecular etiology and genotype-phenotype correlation of WS in 36 Chinese Han deaf probands and 16 additional family members that were clinically diagnosed with WS type I (WS1, n = 8) and type II (WS2, n = 42). Mutation screening of six WS-associated genes detected PAX3 mutations in 6 (86%) of the 7 WS1 probands. Among the 29 WS2 probands, 13 (45%) and 10 (34%) were identified with SOX10 and MITF mutations, respectively. Nineteen of the 26 detected mutations were novel. In WS2 probands whose parental DNA samples were available, de novo mutations were frequently seen for SOX10 mutations (7/8) but not for MITF mutations (0/5, P = 0.005). Excessive freckle, a common feature of WS2 in Chinese Hans, was frequent in WS2 probands with MITF mutations (7/10) but not in those with SOX10 mutations (0/13, P = 4.9 × 10−4). Our results showed that mutations in SOX10 and MITF are two major causes for deafness associated with WS2. These two subtypes of WS2 can be distinguished by the high de novo rate of the SOX10 mutations and the excessive freckle phenotype exclusively associated with the MITF mutations.

Identification of a de novo mutation of SOX10 in a Chinese patient with Waardenburg syndrome type IV

ObjectivesWaardenburg syndrome is a rare genetic disorder, characterized by the association of sensorineural hearing loss and pigmentation abnormalities. Four subtypes have been classified. The present study aimed to analyze the clinical feature and investigate the genetic cause for a Chinese case of Waardenburg type IV (WS4). MethodsThe patient and his family members were subjected to mutation detection in the candidate gene SOX10 by Sanger sequencing. ResultsThe patient has the clinical features of WS4, including sensorineural hearing loss, bright blue irides, premature graying of the hair and Hirschsprung disease. A novel heterozygous frameshift mutation, c.752_753ins7 (p.Gly252Alafs*31) in the exon 5 of SOX10 was detected in the patient, but not found in the unaffected family members and 100 normal controls. This mutation results in a premature stop codon 31 amino acid downstream. ConclusionsThe novel mutation c.752_753ins7 (p.Gly252Alafs*31) arose de novo and was considered as the cause of WS4 in the proband. This study further characterized the molecular complexity of WS4 and provided a clinical case for genotype-phenotype correlation studies of different phenotypes caused by SOX10 mutations.

Skip segment Hirschsprung's disease in a patient with Shah-Waardenburg Syndrome

Abstract Introduction We present a new case of Skip segment Hirschsprung's disease (SSHD) associated to Waardenburg's syndrome, in a patient with total colonic aganglionosis (TCA). Even though there are more than 30 cases reported in the literature, SSHD's existence is controversial, due to the fact that there is not clear embriological theory to explain this phenomenon. Case report 20 months-old male patient, that at four days-old had a temporary ileostomy because of an episode of intestinal obstruction. A microileum and right microcolon was observed at the moment of surgery. Biopsies of the ileum and microcolon confirmed the aganglionism. At four months-old definitive surgery was performed according to Boley's procedure. Hystopathological study of the surgical piece showed absence of ganglion cells in cecum and ascending colon (SSHD). The postoperatory has been favorable. A mutation in SOX10 gen was objectified in the molecular study, that confirmed the Shah Waardenburg syndrome. Discussion Most of cases of SSHD were observed in patients with TCA, as in our case. These patients usually need a temporary stoma before the definitive surgery. We think that the only way to discover SSHD cases is to make extended biopsies in left, transverse and right colon, and in ileum, while performing the ileostomy or in the definitve surgery. Conclusion SSHD must be included as a new phenotype in Hirschsprung spectrum. Preservation of these intestinal segments can improve intestinal function, specially in patients with TCA.

Outcomes of evaluation and testing of 660 individuals with hearing loss in a pediatric genetics of hearing loss clinic.

Hearing loss is a relatively common condition in children, occurring in approximately 2 out of every 1,000 births with approximately 50% of reported diagnoses having a primary genetic etiology. Given the prevalence and genetic component of hearing loss, coupled with a trend toward early diagnosis with the institution of universal newborn hearing screening, The Genetics of Hearing Loss Clinic was established at The Children's Hospital of Philadelphia to manage the diagnosis, testing, and genetic counseling for individuals and families. This paper described a cohort of 660 individuals with a diagnosis of hearing loss evaluated between July 2008 and July 2015 in the Genetics of Hearing Loss Clinic. To elucidate the cause of hearing loss in this cohort for better management and prognostication, testing included single nucleotide polymorphism chromosomal microarray, hearing loss next generation sequencing panel, and additional clinical tests inclusive of thyroid and renal function studies, temporal bone magnetic resonance imaging, and electrocardiogram. Of those evaluated, most had bilateral sensorineural hearing loss, occurring in 489/660 (74%). Additionally, 612/660 (93%) of patients presented with a nonsyndromic form of hearing loss (no other observed clinical findings at the time of exam), of which pathogenic mutations in GJB2 were most prevalent. Of the individuals with syndromic manifestations (48/660), Usher and Waardenburg syndrome were most commonly observed. A family history of hearing loss (first degree relative) was present in 12.6% of families with available information. Through molecular analyses, clinical examination, and laboratory testing, a definitive etiologic diagnosis was established in 157/660 (23.8%) of individuals. © 2016 Wiley Periodicals, Inc.

Molecular pathogenesis of Waardenburg syndrome type II resulting from SOX10 gene mutation

To explore the molecular mechanism of Waardenburg syndrome type II (WS2) resulting from SOX10 gene mutation E248fs through in vitro experiment. 293T cells were transiently transfected with wild type (WT) SOX10 and mutant type (MT) E248fs plasmids. The regulatory effect of WT/MT SOX10 on the transcriptional activity of MITF gene and influence of E248fs on WT SOX10 function were determined with a luciferase activity assay. The DNA binding capacity of the WT/MT SOX10 with the promoter of the MITF gene was determined with a biotinylated double-stranded oligonucleotide probe containing the SOX10 binding sequence cattgtc to precipitate MITF and E248fs, respectively. The stability of SOX10 and E248fs were also analyzed. As a loss-of-function mutation, the E248fs mutant failed to transactivate the MITF promoter as compared with the WT SOX10 (P<0.01), which also showed a dominant-negative effect on WT SOX10. The WT SOX10 and E248fs mutant were also able to bind specifically to the cattgtc motif in the MITF promoter, whereas E248fs had degraded faster than WT SOX10. Despite the fact that the E248fs has a dominant-negative effect on SOX10, its reduced stability may down-regulate the transcription of MITF and decrease the synthesis of melanin, which may result in haploinsufficiency of SOX10 protein and cause the milder WS2 phenotype.

A de novo silencer causes elimination of MITF-M expression and profound hearing loss in pigs.

BackgroundGenesis of novel gene regulatory modules is largely responsible for morphological and functional evolution. De novo generation of novel cis-regulatory elements (CREs) is much rarer than genomic events that alter existing CREs such as transposition, promoter switching or co-option. Only one case of de novo generation has been reported to date, in fish and without involvement of phenotype alteration. Yet, this event likely occurs in other animals and helps drive genetic/phenotypic variation.ResultsUsing a porcine model of spontaneous hearing loss not previously characterized we performed gene mapping and mutation screening to determine the genetic foundation of the phenotype. We identified a mutation in the non-regulatory region of the melanocyte-specific promoter of microphthalmia-associated transcription factor (MITF) gene that generated a novel silencer. The consequent elimination of expression of the MITF-M isoform led to early degeneration of the intermediate cells of the cochlear stria vascularis and profound hearing loss, as well as depigmentation, all of which resemble the typical phenotype of Waardenburg syndrome in humans. The mutation exclusively affected MITF-M and no other isoforms. The essential function of Mitf-m in hearing development was further validated using a knock-out mouse model.ConclusionsElimination of the MITF-M isoform alone is sufficient to cause deafness and depigmentation. To our knowledge, this study provides the first evidence of a de novo CRE in mammals that produces a systemic functional effect.Electronic supplementary materialThe online version of this article (doi:10.1186/s12915-016-0273-2) contains supplementary material, which is available to authorized users.

Paediatric Cochlear Implantation in Patients with Waardenburg Syndrome

Objective: To analyse the benefit of cochlear implantation in young deaf children with Waardenburg syndrome (WS) compared to a reference group of young deaf children without additional disabilities. Method: A retrospective study was conducted on children with WS who underwent cochlear implantation at the age of 2 years or younger. The post-operative results for speech perception (phonetically balanced standard Dutch consonant-vocal-consonant word lists) and language comprehension (the Reynell Developmental Language Scales, RDLS), expressed as a language quotient (LQ), were compared between the WS group and the reference group by using multiple linear regression analysis. Results: A total of 14 children were diagnosed with WS, and 6 of them had additional disabilities. The WS children were implanted at a mean age of 1.6 years and the 48 children of the reference group at a mean age of 1.3 years. The WS children had a mean phoneme score of 80% and a mean LQ of 0.74 at 3 years post-implantation, and these results were comparable to those of the reference group. Only the factor additional disabilities had a significant negative influence on auditory perception and language comprehension. Conclusions: Children with WS performed similarly to the reference group in the present study, and these outcomes are in line with the previous literature. Although good counselling about additional disabilities concomitant to the syndrome is relevant, cochlear implantation is a good rehabilitation method for children with WS.

Mutation analysis of seven patients with Waardenburg syndrome

To perform genetic analysis for 7 patients with Waardenburg syndrome. Potential mutation of MITF, PAX3, SOX10 and SNAI2 genes was screened by polymerase chain reaction and direct sequencing. Functions of non-synonymous polymorphisms were predicted with PolyPhen2 software. Seven mutations, including c.649-651delAGA (p.R217del), c.72delG (p.G24fs), c.185T>C (p.M62T), c.118C>T (p.Q40X), c.422T>C (p.L141P), c.640C>T (p.R214X) and c.28G>T(p.G43V), were detected in the patients. Among these, four mutations of the PAX3 gene (c.72delG, c.185T>C, c.118C>T and c.128G>T) and one SOX10 gene mutation (c.422T>C) were not reported previously. Three non-synonymous SNPs (c.185T>C, c.128G>T and c.422T>C) were predicted as harmful. Genetic mutations have been detected in all patients with Waardenburg syndrome.

Waardenburg syndrome type II in a Chinese patient caused by a novel nonsense mutation in the SOX10 gene

ObjectiveWaardenburg syndrome is a congenital genetic disorder. It is the most common type of syndromic hearing impairment with highly genetic heterogeneity and proved to be related by 6 genes as follows: PAX3, MITF, SNAI2, EDN3, EDNRB and SOX10. This article aims to identify the genetic causes of a Chinese WS child patient. MethodsA Chinese WS child was collected for clinical data collection by questionnaire survey. DNA samples of proband and his parents were extracted from peripheral blood samples. Six candidate genes were sequenced by the Trusight One sequencing panel on the illumina NextSeq 500 platform. ResultsA novel nonsense heterozygous mutation was found in the coding region of exon 2 in the SOX10 gene of proband. The novel nonsense heterozygous mutation could cause the replacement of the 55th lysine codon by stop codon (484T > C, C142R) and further more possibly cause terminating the protein translation in advance. However, both proband's parents had no mutation of genes above mentioned. ConclusionThe gene mutation of SOX10 [NM_006941.3 c.163A > T] is a novel nonsense mutation. No record of this mutation has been found in dbSNP, HGMD, 1000 Genomes Project, ClinVar and ESP6500 databases. It meets the condition of PS2 of strong evidence in 2015 ACMG Standards and Guidelines.

Application of a New Genetic Deafness Microarray for Detecting Mutations in the Deaf in China.

ObjectiveThe aim of this study was to evaluate the GoldenGate microarray as a diagnostic tool and to elucidate the contribution of the genes on this array to the development of both nonsyndromic and syndromic sensorineural hearing loss in China.MethodsWe developed a microarray to detect 240 mutations underlying syndromic and nonsyndromic sensorineural hearing loss. The microarray was then used for analysis of 382 patients with nonsyndromic sensorineural hearing loss (including 15 patients with enlarged vestibular aqueduct syndrome), 21 patients with Waardenburg syndrome, and 60 unrelated controls. Subsequently, we analyzed the sensitivity, specificity, and reproducibility of this new approach after Sanger sequencing-based verification, and also determined the contribution of the genes on this array to the development of distinct hearing disorders.ResultsThe sensitivity and specificity of the microarray chip were 98.73% and 98.34%, respectively. Genetic defects were identified in 61.26% of the patients with nonsyndromic sensorineural hearing loss, and 9 causative genes were identified. The molecular etiology was confirmed in 19.05% and 46.67% of the patients with Waardenburg syndrome and enlarged vestibular aqueduct syndrome, respectively.ConclusionOur new mutation-based microarray comprises an accurate and comprehensive genetic tool for the detection of sensorineural hearing loss. This microarray-based detection method could serve as a first-pass screening (before next-generation-sequencing screening) for deafness-causing mutations in China.