A common mitochondrial DNA mutation in the t-RNA(Lys) of patients with myoclonus epilepsy associated with ragged-red fibers.

摘要: Nucleotide sequence analyses of muscle mitochondrial DNA (mtDNA) from a patient with myoclonus epilepsy associated ragged-red fibers (MERRF) revealed 33 single base substitutions, including 23 in coding regions for polypeptides and 10 non-coding regions, as compared the normal human mtDNA sequence. Three COI, ND4, Cytb, would result amino acid which are conserved among species. Of three patients MERRF, all had an identical A to G substitution only at nucleotide position 8344 t-RNA(Lys) region. The was not found 15 controls. Various degrees combined enzymic defects oxidative phosphorylation system mitochondria were MERRF patients. could be explained by altered function or processing mutant t-RNA(Lys). This mutation is most probable cause MERRF.