Identification of a MYO7A mutation in a large Chinese DFNA11 family and genotype-phenotype review for DFNA11.

BACKGROUND: The molecular and genetic research showed the association between DFNA11 and mutations in MYO7A. This research aimed to identify a MYO7A mutation in a family with nonsyndromic autosomal dominant hearing loss.

METHODS: We have ascertained one large multigenerational Chinese family (Z029) with autosomal dominant late-onset progressive non-syndromic sensorineural hearing loss. Genome-wide linkage analysis of the family mapped the disease locus to the DFNA11 interval, where the MYO7A was considered as a candidate gene. Sequencing of the PCR products was carried out for each sample. One hundred and fifty one control subjects with normal hearing functions were also evaluated.

RESULTS: The pathogenic mutation (c.2011G>A) was identified in the family. This mutation co-segregated with hearing loss in this family. No mutation of MYO7A gene was found in the 151 controls.

CONCLUSIONS: The missense mutation of MYO7A is identified in the family displaying the pedigree consistent with DFNA11. We not only examined the clinical and genetic characteristics of the family, but also provided a basis for genetic counseling. We also summarized and analyzed the phenotypes and genotypes of all DFNA11 families, four of nine are Chinese families, suggesting that MYO7A mutations are not rare. Therefore, we should pay more attention to Chinese patients.