Connexin mutation testing of children with nonsyndromic, autosomal recessive sensorineural hearing loss

OBJECTIVE: The etiology of hearing loss is heterogeneous and falls into the two broad categories of genetic and environmental. In the genetic subgroup, 70% are non syndromic. Fifty percent of nonsyndromic sensorineural deafness is due to a mutation in the connexin 26 gene. This article presents the detection rate of connexin mutations in a multiethnic Canadian population. METHODS: A study of patients with nonsyndromic hearing loss seen over a period of 2 years who had connexin 26 mutation testing. RESULTS: Nine of the 18 patients had connexin 26 mutations. CONCLUSION: The majority of our patients with connexin 26 mutations had moderate to profound hearing loss. Testing for connexin mutations should be standard care because it accounts for a large proportion of individuals with nonsyndromic hearing loss. Reasons for testing include ruling out a syndromic cause, predicting moderate to profound hearing loss, and the need for language intervention, cochlear implants, and genetic counselling.