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GTR Home > Conditions/Phenotypes > Autosomal dominant nonsyndromic hearing loss 2A


DFNA2 nonsyndromic hearing loss is characterized by symmetric, predominantly high-frequency sensorineural hearing loss (SNHL) that is progressive across all frequencies. At younger ages, hearing loss tends to be mild in the low frequencies and moderate in the high frequencies; in older persons, the hearing loss is moderate in the low frequencies and severe to profound in the high frequencies. Although the hearing impairment is often detected during routine hearing assessment of a school-age child, it is likely that hearing is impaired from birth, especially at high frequencies. Most affected persons initially require hearing aids to assist with sound amplification between ages ten and 40 years. By age 70 years, all persons with DFNA2 nonsyndromic hearing loss have severe-to-profound hearing impairment. [from GeneReviews]

Available tests

22 tests are in the database for this condition.

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Genes See tests for all associated and related genes

  • Also known as: DFNA2, DFNA2A, KV7.4, KCNQ4
    Summary: potassium voltage-gated channel subfamily Q member 4

Clinical features


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