GJB2 allele variants and the associated audiologic features identified in Chinese patients with less severe idiopathic hearing loss.

Aims: To explore possible correlations between the genotype of GJB2, the gene that encodes connexin 26 (Cx26), and its related audiogram features in Chinese patients with less severe nonsyndromic hearing loss (HL), we examined the pure tone audiograms and GJB2 coding region allele variants in 236 patients. Results: Twelve of 34 (35.3%) patients with biallelic GJB2 mutations had totally asymmetric HL, a significantly higher prevalence than in patients with wild-type GJB2 (p = 0.027). In patients with biallelic GJB2 mutations, the percentages of cases with sloping, flat, and differently shaped audiograms between ears were 44.1%, 11.8%, and 35.3%, respectively; however, in patients with wild-type GJB2, the percentages were 72.4%, 3.4%, and 21.1%, respectively. Significant differences were found between patients with wild-type GJB2 and those with biallelic GJB2 mutations (p = 0.013) as well as those with single GJB2 mutations (p = 0.043). Threshold differences between ears were significantly higher in patient...