Sequence analysis of mitochondrial DNA mutations in a maternally transmitted non-syndromic deafness family

Objective: To investigate the association between mitochondrial DNA mutations and inherited deafness through sequence analysis of mitochondrial DNA 12SrRNA and tRNA^Ser（UCN） genes in a maternally transmitted non-syndromic deafness family. Methods: The diagnosis was validated by hearing test.Blood samples from the pedigree（6 members） were obtained.DNA was extracted from the leukocytes. The mitochondrial DNA target fragments were amplified by poly merase chain reaction（PCR）.The PCR products were analyzed by sequencing. Computerized 12SrRNA secondary structure modeling was carried up to identify mutants found in this study's contribution. Results: All samples examined carried mtDNA A1555G、G1007A、A1313G mutations in 12SrRNA gene.Computerized modeling shows that the 3 mutations made the 12SrRNA secondary structure totally different,and the energy changes a lot. Conclusions:The mtDNA A1555G、G1007A、A1313G mutations might relate to the pathogenesis of maternally transmitted non-syndromic deafness.