Frequency of SLC26A4 IVS7-2A>G mutation in patients with severe to profound hearing loss from different area and ethnic group in China

Objective To carry out molecular epidemiology study of SLC26A4 IVS7-2 AG mutation in large Chinese deaf population and to provide evidence for fast screening and gene diagnosis of enlarged vestibular aqueduct syndrome(EVAS).Methods A total of 1979 patients with non-syndromic hearing loss(NSHL)underwent questionnaire and PCR for IVSAG mutation detection of SLC26A4 gene. Results All 245 patients(12.38%)with homozygotous and heterozygotous IVS7-2 AG mutation were found among the 1979 NSHL.It showed statistically significant difference among north and northeast, northwest,east and southeast,southwest and central area in China.(X~2=34.4899,P0.05). Carrier frequency of the central area(27.52% )was notably higher than southwest area(6.69%).The IVS7-2 A G mutation was most frequently found in Han deaf groups(13.88%).Tibetan,Hui,and other western minorities were lower than Han deaf population(X~2=35.4456,P0.05).Conclusions A high SLC26A4 IVS7-2 AG mutation frequency for deafness in Chinese patients was found.Detection of the pathogenic mutations was bringing the possibility to detect EVAS at an early stage.Moreover,it might help to establish diverse diagnostic strategies toward differently ethical deaf population in different region of China.