[DNA microarray screening analysis in children with profound hearing impairment in Hubei province]

To investigate characteristics of molecular etiology of children with profound sensorineural hearing loss in Hubei province, and to provide reference for deafness treatment and genetic counseling.

Three hundred and six children with profound sensorineural hearing loss in Hubei province were enrolled, their genomic DNA were extracted from peripheral blood and a deafness gene test chip was used to screen nine hot spot mutation in the GJB2, GJB3, SLC26A4, and mitochondria 12SrRNA gene. All patients with SLC26A4 gene mutation were given temporal bone CT scan.

One hundred and thirty-two (43.14%) out of 306 children were found carrying at least one pathogenic gene mutation. The mutation rates of GJB2, SLC26A4 and mitochondria DNA 12SrRNA gene were 29.41% (90/306), 13.72% (42/306) and 0.65% (2/306), respectively. None out of 306 children was detected GJB3 gene mutation. Thirty-six patients carrying SLC26A4 gene mutation were detected enlarged vestibular aqueduct by CT scan.

Mutations of GJB2 and SLC26A4 gene are two major pathogenic gene for genetic hearing loss in children. 235delC mutation is the main mutation type, followed by IVS7-2A> G mutation type. The screening of SLC26A4 gene common mutations contribute to the diagnosis of enlarged vestibular aqueduct syndrome.