title: Leber's hereditary optic neuropathy is associated with the mitochondrial ND6 T14484C mutation in three Chinese families.
abstract: We report here the clinical, genetic, and molecular characterization of three Chinese families with maternally transmitted Leber's hereditary optic neuropathy (LHON). Clinical and genetic evaluations revealed the variable severity and age-of-onset in visual impairment in these families. In the affected matrilineal relatives, the loss of central vision is bilateral, the fellow eye becoming affected either simultaneously (45%) or sequentially (55%). The penetrances of vision loss in these pedigrees were 27%, 50%, and 60%, respectively. The age-at-onset of vision loss in these families was 14, 19, and 24 years, respectively. Furthermore, the ratios between affected male and female matrilineal relatives were 1:1, 1:1.2, and 1:2, respectively. Mutational analysis of mitochondrial DNA revealed the presence of homoplasmic ND6 T14484C mutation, which has been associated with LHON. The incomplete penetrance and phenotypic variability implicate the involvement of nuclear modifier gene(s), environmental factor(s) or mitochondrial haplotype(s) in the phenotypic expression of the LHON-associated T14484C mutation in these Chinese pedigrees.
authors.affiliation: Department of Ophthalmology, Dongfang Hospital, Beijing University of Chinese Medicine and Pharmacology, China.
authors.forename: Yan-Hong
authors.initials: YH
authors.lastname: Sun
authors.forename: Qi-Ping
authors.initials: QP
authors.lastname: Wei
authors.forename: Xiangtian
authors.initials: X
authors.lastname: Zhou
authors.forename: Yaping
authors.initials: Y
authors.lastname: Qian
authors.forename: Jian
authors.initials: J
authors.lastname: Zhou
authors.forename: Fan
authors.initials: F
authors.lastname: Lu
authors.forename: Jia
authors.initials: J
authors.lastname: Qu
authors.forename: Min-Xin
authors.initials: MX
authors.lastname: Guan
mesh_terms: D002681:China / Q000453:epidemiology; D015897:Comorbidity; D004252:DNA Mutational Analysis; D004272:DNA, Mitochondrial / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000453:epidemiology / Q000235:genetics; D006579:Heterozygote; D006801:Humans; D008297:Male; D009154:Mutation; D029242:Optic Atrophy, Hereditary, Leber / Q000453:epidemiology* / Q000235:genetics*; D010375:Pedigree; D019683:Penetrance; D015995:Prevalence; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D014786:Vision Disorders / Q000453:epidemiology* / Q000235:genetics*
chemical_list: D004272:DNA, Mitochondrial