Unveiling a novel GJB2 dominant K22T mutation in a Chinese family with hearing loss

• Identified a novel heterozygous dominant GJB2 mutation (c.65T>G, p.K22T) in a Chinese family with non-syndromic hearing loss, expanding the mutation spectrum of GJB2. • Next-generation sequencing of 129 deafness-related genes revealed the mutation segregating with the phenotype, strongly supporting its pathogenicity. • Structural analysis predicted disruption of hydrogen bond and electrostatic interactions in the Cx26 gap junction channel, consistent with in silico predictions from PolyPhen and SIFT. • Findings underscore the importance of screening for dominant GJB2 mutations in familial hearing loss, with implications for genetic diagnosis and therapeutic strategies.