Objective: To investigate the etiology of deafness and the common disease-causing genes among patients with sensorineural hearing loss in Nangtong and to explore the proportion of genetic factors in this region.
Method: One hundred and fifty cases with hearing loss from three schools for deaf-mutes in Nangtong received sequence analysis of GJB2, GJB3, SLC26A4, mtDNA12SrRNA and mtDNA tRNASer(UCN), and individuals carrying SLC26A4 mutation were given further temporal bone CT scan. We investigated the etiology of deafness by analyzing the genes testing results and questionnaires.
Result: GJB2 mutations were responsible for approximately 19.33% of the cases in Nangtong area. Nineteen cases (12.67%) were diagnosed with EVA (enlarged vestibular aqueduct) by screening SLC26A4 followed by temporal bone CT scan. The aminoglycoside-related mtDNA 1555A > G mutation accounted for 2.67% (4/150) of the cases in this area. In addition, 27 cases (18%) may relate to genetic factors in this group.
Conclusion: By genetic screening we find that genetic deafness occupies a large proportion in deaf community. Our data demonstrate that gene testing has important role in clarifying etiology for hearing loss population.