A Genetic AnaIysis of 800 Non-syndromic Deafness Patients from Shanxi Province / 听力学及言语疾病杂志

ABSTRACT

Objective The patients with non-syndromic deafness in Shanxi Province were retrospectively an_alyzed for the common deafness gene mutations and frequency of mutations carrying rate ,to understand the molecu_lar pathogenesis of deafness in Shanxi area .Methods Genomic DNAs of 800 patients of non -syndromic deafness within Shanxi were obtained from peripheral blood .Genes GJB2 ,GJB3 ,SLC26A4 and mitochondrial 12SrRNA 1494 and 1555 loci were sequenced after polymerase chain reaction (PCR) amplification and compared with the NCBI website for the analysis of the formation of mutations .ResuIts Among 800 patients ,353 cases (44 .13% ) showed detected deafness related mutations and the genetic etiology was found for 294 patients (36 .75% ) .Among them , 153 cases (19 .13% ) carried double allele mutations in the GJB2 gene .The most frequent mutation of GJB2 gene was 235delC ,and the carrying rate was 13 .5% (216/1 600) .The double mutant allele of SLC26A4 gene was detec_ted in 123 cases (15 .38% ) ,and the most common mutation was IVS7-2A>G ,identified in 7 .44% (119/1 600) of patients .Homogenic mitochondrial 12S rRNA 1494C> T mutation in one patient and 1555A> G mutation in 15 patients were detected .GJB3 gene c .538C > T heterozygous mutation was found in two patients .Altogether , 36 .75% (294/800) of patients with deafness were caused by gene mutations .ConcIusionThe data containing GJB2 gene and SLC26A4 gene carrying rate are consistent with the published data of non-syndromic deafness in the Northwest region of China ,but the carrying rate of mitochondrial gene mutations is lower than the average level of China .Our data show that the gene mutations contribute to 36 .75% of etiology in patients with deafness .This study reflects the importance of deafness related genes screening in Shanxi area for early diagnosis and genetic con_sultation .