Analysis On Mutation Of The Deafness Gene GJB2 And Clinical Application

Partâ… Mutational Analysis of the GJB2 on Hereditary DeafnessObjective: To analysis the mutation's frequency and type of GJB2 gene in deafness patients in Suzhou, to provide evidence for the clinical application.Methods: We collected eighty-five sporadic deafness patients and 100 controls. DNA was extracted from the blood of each sample. GJB2 gene was amplified by PCR, the PCR product sequence was analyzed.Results: We detect 11 different mutations in eighty-five sporadic deafness patients, including three deletions ,235delC,176-191del16 and 299-300delAT which caused frameshift; two missense mutations V37Iand E47X; one nonsense mutation and five polymorphisms V27I,E114G,I203T,V190V and T86R; 176-191del16,E47X,V190V and T86R have not been reported in Chinese deafness patients.235delC mutation was the most prevalent mutation and the allele frequency rate was 24.1%, seventeen cases were homozygous for 235delC/235delC. In control group we found V27I,V37I,E114G,299-300delAT and T123N, The V27I and E114G were the most frequent type of polymorphisms and the allele frequency were 28% and 12%, respectively.Conclusion: GJB2 gene mutation was the most prevalent pathologic cause in non-syndromic hearing loss, twenty-four patients have definitely pathologic mutation on GJB2 gene in eighty-five patients (28.2%). The results of this study have important implications for genetic diagnostic testing for deafness in the clinic.