[Mitochondrial DNA mutation analysis in 97 Chinese patients with mitochondrial cephalomyopathy].
OBJECTIVE
To investigate the characteristics of mitochondrial DNA mutations and genotype-phenotype correlations in mitochondrial encephalomyopathies.


METHODS
Biopsy of skeletal muscle and collection of peripheral blood samples were conducted among 97 patients with mitochondrial encephalomyopathies. Southern blotting, PCR-RFLP and direct sequencing of PCR products were performed to search large scale deletions, and common and uncommon pathological point mutations in the muscle and/or blood mtDNA.


RESULTS
Seventy-seven patients were identified to be with mitochondrial DNA mutations, including single large deletion (n = 21), multiple large-scale deletions (n = 4), A3243G point mutation (n = 43), A8344G point mutation (n = 6), T8993G mutation (n = 1), T8993C mutation (n = 1), and T3271C mutation (n = 1). Total mtDNA sequencing revealed 4 different novel point mutations in four unrelated patients with isolated mitochondrial myopathy.


CONCLUSIONS
The type and frequency of mtDNA mutations in this series of Chinese mitochondrial encephalopathies are consistent with those reported abroad, Although there is some association between the genotype and phenotype, heterogeneity in phenotype and genotype is also a prominent feature seen in this series of patients, especially those with A3243G mutation.
Wang
Zhao-xia
ZX
Department of Neurology, First Hospital of Peking University, Beijing 100034, China. drwangzx@yahoo.com.cn
Luan
Xing-hua
XH
Zhang
Ying
Y
Yang
Yan-ling
YL
Qi
Yu
Y
Bu
Ding-fang
DF
Yuan
Yun
Y
D000293:Adolescent; D000328:Adult; D044466:Asian People; D002648:Child; D002675:Child, Preschool; D004252:DNA Mutational Analysis; D004272:DNA, Mitochondrial / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D017237:Mitochondrial Encephalomyopathies / Q000208:ethnology / Q000235:genetics* / Q000473:pathology*; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length
D004272:DNA, Mitochondrial