Gene mutations of mitochondrial DNA in a family with MELAS

Objective To investigate the mutations of mitochondrial DNA(mt DNA) in a family pedigree of mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes(MELAS).Methods The peripheral blood of 2 patients with MELAS and 100 healthy people(control group) was collected.PCR was used to amplify the whole tRNA genes of 22 mitochondria,which were then screened by denaturing high-performance liquid chromatography.The tRNA gene with abnormal spike was sequenced,and the mutation site was determined.Results Compared with control group,there was a heteroplasmic A1640T/A mutation in tRNA-Val gene in patients with MELAS.ConclusiontRNA-Val gene mutation A1640T/A of mtDNA in a family pedigree of MELAS might be a pathogeny of MELAS.