Different effects of novel mtDNA G3242A and G3244A base changes adjacent to a common A3243G mutation in patients with mitochondrial disorders.
Two novel mitochondrial DNA base changes were identified at both sides of the 3243A>G mutation, the most common mutation associated with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). One was a 3244G>A transition in a girl with MELAS. The other was a 3242G>A transition in a girl with a mitochondrial disorder without a MELAS phenotype. Although the two base changes were adjacent to the 3243A>G mutation, they had different effects on the clinical phenotype, muscle pathology, and respiratory chain enzyme activity. Investigations of the different effects of the 3244G>A and 3242G>A base changes may provide a better understanding of tRNA dysfunction in mitochondrial disorders.
Mimaki
Masakazu
M
Department of Mental Retardation and Birth Defect Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawahigashi, Kodaira, Tokyo, Japan.
Hatakeyama
Hideyuki
H
Ichiyama
Takashi
T
Isumi
Hiroshi
H
Furukawa
Susumu
S
Akasaka
Manami
M
Kamei
Atsushi
A
Komaki
Hirofumi
H
Nishino
Ichizo
I
Nonaka
Ikuya
I
Goto
Yu-ichi
Y
D002648:Child; D002675:Child, Preschool; D004272:DNA, Mitochondrial / Q000235:genetics*; D005260:Female; D006801:Humans; D017241:MELAS Syndrome / Q000235:genetics; D028361:Mitochondrial Diseases / Q000235:genetics*; D017354:Point Mutation; D011110:Polymorphism, Genetic
D004272:DNA, Mitochondrial