title: [Study on three common mitochondrial DNA mutations in Leber's hereditary optic neuropathy].
abstract: OBJECTIVE
  To screen for genetic mutations in 35 patients with Leber's hereditary optic neuropathy (LHON).
  
  
  METHODS
  Polymerase chain reaction and DNA sequencing were used to screen for the presence of mitochondrial DNA mutations.
  
  
  RESULTS
  The total detection rate of top 3 common LHON mutations were 20.0%, which included 6 cases of ND4 11778 G to A, 1 case of ND1 3460 G to A. No ND6 14484 T to C mutation was detected. A ND4 G11719A synonymous mutation was found in all patients. In addition, 21 other mutations were discovered among 23 patients, among which 13 had a single mutation, 8 had a second mutations, and 2 had a third mutation. Among the 21 mutations, ND4 11778 G to A had a frequency of 28.6%(6/21). ND1 3552 T to A, ND6 14470 T to C, ND4 11794 T to C, ND1 3497 C to T and 3644 T to C respectively had a frequency of 19.0% (4/21), 19.0%(4/21), 14.3%(3/21), 9.5%(2/21) and 9.5%(2/21). Among the 3 patients who harbored a ND4 11794 T to C mutation, 2 were heteroplasmic and one was homoplasmic in nature.
  
  
  CONCLUSIONS
  The ND4 11778 G to A mutation is common in the Top "3" primary mutations of patients with LHON. Candidate LHON mutation ND1 3552 T to A or ND1 3644 T to C resulted in LHON pathogenesis as single or synergistic effect. The visual impairment at onset of the disease with candidate mutation were better than the eyes with the ND4 11778 G to A mutation.
authors.affiliation: Department of Clinical Laboratory, Taiyuan City Centre Hospital, Taiyuan, Shanxi, People's Republic of China. yunxiama1981@yahoo.com
authors.forename: Yun-xia
authors.initials: YX
authors.lastname: Ma
authors.forename: Yon-gan
authors.initials: YG
authors.lastname: Zhou
authors.forename: Jing-ping
authors.initials: JP
authors.lastname: Zhang
authors.forename: Quan-bin
authors.initials: QB
authors.lastname: Zhang
authors.forename: Wei-la
authors.initials: WL
authors.lastname: Liu
authors.forename: Cai-fen
authors.initials: CF
authors.lastname: Ren
authors.forename: Xiao-yu
authors.initials: XY
authors.lastname: Li
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004272:DNA, Mitochondrial / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D029242:Optic Atrophy, Hereditary, Leber / Q000235:genetics*
chemical_list: D004272:DNA, Mitochondrial