title: Two compound frame-shift mutations in succinate dehydrogenase gene of a Chinese boy with encephalopathy.
abstract: OBJECTIVE
  To investigate respiratory chain complex II deficiency resulted from mutation in succinate dehydrogenase gene (SDH) encoding complex II subunits in China.
  
  
  METHODS
  An 11-year-old boy was admitted to our hospital. He had a history of progressive psychomotor regression and weakness since the age of 4years. His cranial magnetic resonance imaging revealed focal, bilaterally symmetrical lesions in the basal ganglia and thalamus, indicating mitochondrial encephalopathy. The activities of mitochondrial respiratory chain enzymes I-V in peripheral leukocytes were determined via spectrophotometry. Mitochondrial DNA and the succinate dehydrogenase A (SDHA) gene were analyzed by direct sequencing.
  
  
  RESULTS
  Complex II activity in the leukocytes had decreased to 33.07nmol/min/mg mitochondrial protein (normal control 71.8±12.9); the activities of complexes I, III, IV and V were normal. The entire sequence of the mitochondrial DNA was normal. The SDHA gene showed two heterozygous frame-shift mutations: c.G117G/del in exon 2 and c.T220T/insT in exon 3, which resulted in stop codons at residues 56 and 81, respectively.
  
  
  CONCLUSIONS
  We have described the first Chinese case of mitochondrial respiratory chain complex II deficiency, which was diagnosed using enzyme assays and gene analysis. Two novel, compound, frame-shift mutations, c.G117G/del in exon 2 and c.T220T/insT in exon 3 of the SDHA gene, were found in our patient.
authors.affiliation: Department of Pediatrics, Chinese Liberation Army General Hospital, Beijing, PR China.
authors.forename: Yan-Yan
authors.initials: YY
authors.lastname: Ma
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, PR China.
authors.forename: Tong-Fei
authors.initials: TF
authors.lastname: Wu
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, PR China.
authors.forename: Yu-Peng
authors.initials: YP
authors.lastname: Liu
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, PR China.
authors.forename: Qiao
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, PR China.
authors.forename: Xi-Yuan
authors.initials: XY
authors.lastname: Li
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, PR China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Ding
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, PR China.
authors.forename: Jin-Qing
authors.initials: JQ
authors.lastname: Song
authors.affiliation: Department of Pediatrics, Chinese Liberation Army General Hospital, Beijing, PR China.
authors.forename: Xiu-Yu
authors.initials: XY
authors.lastname: Shi
authors.affiliation: Department of Pediatrics, Chinese Liberation Army General Hospital, Beijing, PR China.
authors.forename: Wei-Na
authors.initials: WN
authors.lastname: Zhang
authors.affiliation: Department of Pediatrics, Chinese Liberation Army General Hospital, Beijing, PR China.
authors.forename: Meng
authors.initials: M
authors.lastname: Zhao
authors.affiliation: Department of Pediatrics, Chinese Liberation Army General Hospital, Beijing, PR China.
authors.forename: Ling-Yan
authors.initials: LY
authors.lastname: Hu
authors.affiliation: Department of Pediatrics, Chinese Liberation Army General Hospital, Beijing, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Ju
authors.affiliation: Clinical Laboratory of Zhongke, Beijing, PR China.
authors.forename: Zhi-Long
authors.initials: ZL
authors.lastname: Wang
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, PR China. Electronic address: amino_acid3003@126.com.
authors.forename: Yan-Ling
authors.initials: YL
authors.lastname: Yang
authors.affiliation: Department of Pediatrics, Chinese Liberation Army General Hospital, Beijing, PR China. Electronic address: zouliping21@hotmail.com.
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Zou
mesh_terms: D001483:Base Sequence; D001921:Brain / Q000473:pathology; D002648:Child; D002681:China; D004252:DNA Mutational Analysis; D042963:Electron Transport Complex II / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D016368:Frameshift Mutation; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008661:Metabolism, Inborn Errors / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D028361:Mitochondrial Diseases / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism / Q000473:pathology
chemical_list: D042963:Electron Transport Complex II; C511268:SDHA protein, human
keywords: Frame-shift mutation; Respiratory chain complex II deficiency; SDHA gene