Gene GJB2
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Also known as
CX26, DFNA3A, DFNB1A, connexin 26, gap junction protein beta 2Overview
GJB2 (Gap Junction Protein Beta 2) encodes connexin 26, a protein that forms gap junctions allowing direct communication between adjacent cells. In the inner ear, connexin 26 is essential for potassium recycling in the cochlea, which is critical for sound transduction. The protein also plays important roles in skin and wound healing.Mutations in GJB2 are the most common cause of genetic hearing loss worldwide, responsible for up to 50% of non-syndromic hereditary deafness in many populations. The carrier frequency for GJB2 mutations can be as high as 1 in 30 in some populations. Some mutations also cause syndromic conditions affecting skin, including keratitis-ichthyosis-deafness syndrome and palmoplantar keratoderma with deafness.
Understanding your GJB2 genetic status is essential for carrier screening and evaluating genetic hearing loss. Identification of GJB2 mutations enables genetic counseling, cochlear implant planning, and monitoring for progressive hearing loss in affected individuals.