Our findings provide further evidence of a correlation between the p.R75Q mutation in Cx26 and a syndromic hearing impairment with palmoplantar keratoderma.
HeLa cells stably expressing wild type Cx26 were transiently transfected to co-express nine individual dominant Cx26 mutants; six associated with non-syndromic hearing loss (W44C, W44S, R143Q, D179N, R184Q, and C202F) and three associated with hearing loss and palmoplantar keratoderma (G59A, R75Q, and R75W).
HeLa cells stably expressing nine dominant Cx26 mutants, six associated with non-syndromic hearing loss (W44C, W44S, R143Q, D179N, R184Q and C202F) and three associated with hearing loss and palmoplantar keratoderma (G59A, R75Q and R75W), individually or together with Cx30, were analyzed by immunocytochemistry, co-immunoprecipitation, and functional assays (scrape-loading and/or fluorescence recovery after photobleaching).
Autosomal dominant prelingual hearing loss with palmoplantar keratoderma syndrome: Variability in clinical expression from mutations of R75W and R75Q in the GJB2 gene.
Interestingly, the novel R75Q mutation affects the same amino acid residue as described recently in a small family (R75W) with profound prelingual hearing loss and PPK.