The coexistence of a Novel ND5 A12340G Mutation with ND1 G3635A Mutation in a Chinese family with Leber hereditary optic neuropathy

　　史小玲 胡正茂 杜利平 金学民 夏昆

　　郑州大学第一附属医院 中国医学遗传学国家重点实验室 450052

　　purpose：to confirm the gene diagonosis of a Chinese family diagnosed LHON in clinic.

　　Method:A five-generation Han Chinese family diagnosed LHON in clinic was studied by clinical examination，genetic evaluation and molecular analysis of mitochondrial DNA.

　　Results:This family was consistent with maternal lineage and there were only 6 of 30 matrilineal relatives who were affected and they were exclusively males，exhibiting a low penetrance of 20%and male predominace.Complete sequence analysis of the proband mitochondrial DNA revealed the homoplasmic reported secondary ND1 G3635A mutation and other 30 variants，belonging to the Asian haplogroup F1.Of these variants，the novel ND5 A12340G mutation absent in 107 unrelated Chinese controls was homoplasmic and have not been reported in the previous leterature.So far，the five-generation Han Chinese family is the sceond family that harbor LHON-associated ND1 G3635A mutation in all the reportd literature.

　　Conclusions:The the novel ND5 A12340G mutation may paly a synergistic role in the penerance and expressivity of LHON with secondary ND1 G3635A Mutation.