[Mitochondrial respiratory chain complex I deficiency due to 10191T>C mutation in ND3 gene].
This study reviews a case of mitochondrial respiratory chain complex I deficiency due to the 10191T>C mutation in mitochondrial ND3 gene. The previously healthy boy progressively presented with blepharoptosis, weakness, epilepsy and motor regression at age 6 years. Elevated blood lactate and pyruvate were observed. Brain magnetic resonance imaging showed symmetrical lesions in the basal ganglia. Leigh syndrome was thus confirmed. The protein from the mitochondria and genomic DNA of the boy and his parents was collected from peripheral blood leucocytes for the activity test for mitochondrial complex I to V and genetic analysis. The results showed the activity of complex I (33.1 nmol /min in 1 milligram mitochondrial protein) was lower than normal reference value (44.0±5.4 nmol /min in 1 milligram mitochondrial protein). The ratio of complex I to citrate synthase (19.8%) was also lower  than normal reference value (48%±11%). The activities of complexes II to V were normal. 10191T>C mutation in ND3 gene of mitochondria was identified in the boy. 10191T>C mutation and complex I deficiency were not detected in his parents. At present, he is 16 years old, and of normal intelligence with spastic paralysis in both lower extremities after treatment. It is concluded that a Chinese boy with isolated complex I deficiency due to 10191T>C mutation in ND3 gene was firstly diagnosed by peripheral leukocytes mitochondrial respiratory chain enzyme assay and gene analysis. This study can provide clinical data for the nosogenesis of Leigh syndrome.
Department of Pediatrics, Peking University First Hospital, Beijing 100034, China.
Yu-Peng
YP
Liu
Yan-Yan
YY
Ma
Tong-Fei
TF
Wu
Qiao
Q
Wang
Qing-Peng
QP
Kong
Xiao-Qiong
XQ
Wei
Yao
Y
Zhang
Jin-Qing
JQ
Song
Xing-Zhi
XZ
Chang
Yue-Hua
YH
Zhang
Jiang-Xi
JX
Xiao
Yan-Ling
YL
Yang
D000293:Adolescent; D001921:Brain / Q000473:pathology; D042967:Electron Transport Complex I / Q000172:deficiency / Q000235:genetics*; D006801:Humans; D007888:Leigh Disease / Q000235:genetics; D008279:Magnetic Resonance Imaging; D008297:Male; D028361:Mitochondrial Diseases / Q000235:genetics*; D009154:Mutation
D042967:Electron Transport Complex I; C114961:MT-ND3 protein, human