Mitochondrial DNA haplogroup Y is associated to Leigh syndrome in Chinese population

State Key Laboratory of Genetic Resources and Evolution, and Yunnan Laboratory of Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
Gene (Impact Factor: 2.14). 10/2012; 512(2). DOI: 10.1016/j.gene.2012.10.054
Source: PubMed


Although Leigh syndrome (LS) is a well characterized clinically mitochondrial disorder, the exact mutation is not found in all cases and it is not clear whether matrilineal background has contributed to this disease. To address this issue, we extensively studied and compared the haplogroup composition of a sample of 171 Chinese LS patients with that of 1597 controls. Our results show that haplogroup Y may increase the risk of LS in Chinese by 2.867 folds (95% CI=1.135-7.240, P=0.020). Haplogroup B5 also has this trend (1.737 folds, 95% CI=0.961-3.139), but with a borderline P-value (P=0.065). Both haplogroups belong to macro-haplogroup N and share a common reverse mutation on nucleotide position 10398 (A10398G). In fact, the combined haplogroup N with 10398G also associated with an increased risk for LS (OR=1.882, 95% CI=1.134-3.124, P=0.013).

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