title: PEMT G523A (V175M) is associated with sporadic Alzheimer's disease in a Chinese population.
abstract: There is evidence that increased concentrations of circulating homocysteine are associated with Alzheimer's disease (AD). Phosphatidylethanolamine N-methyltransferase (PEMT) is an important catalyst involved in the production of homocysteine. We investigated the association of a functional single nucleotide polymorphism (rs7946) in PEMT with sporadic AD risk in a Han Chinese population that included 386 AD patients and 366 controls. PEMT G523A was genotyped by either sequencing or PCR-restriction fragment length polymorphism analysis. The plasma homocysteine concentrations of 210 subjects were determined by high-performance liquid chromatography. Significant higher frequency of the A allele was detected in AD cases than in controls (A vs. G, p = 0.007, OR = 1.482, 95% CI 1.114-1.972). After adjusting for gender, age/age at onset, and APOE ε4 status, logistic analysis showed rs7946 was associated with AD in a dominant model (AA + GA vs. GG, p = 0.007, OR = 1.596, 95% CI 1.138-2.240). When stratified by APOE ε4 status or gender, the significant difference was only observed in the APOE ε4 non-carriers and in the female subjects, respectively. We did not find a relationship of this polymorphism with plasma homocysteine levels. These results suggested that PEMT G523A is associated with AD and that the A allele is an APOE ε4-independent risk factor for AD among Han Chinese women.
authors: National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China.
authors: Xiu-Hua
authors: XH
authors: Bi
authors: Hua-Lu
authors: HL
authors: Zhao
authors: Zhen-Xin
authors: ZX
authors: Zhang
authors: Jun-Wu
authors: JW
authors: Zhang
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000201:enzymology / Q000208:ethnology* / Q000235:genetics*; D019943:Amino Acid Substitution / Q000235:genetics; D044466:Asian People / Q000235:genetics; D002681:China / Q000453:epidemiology; D005260:Female; D056726:Genetic Association Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D050918:Phosphatidylethanolamine N-Methyltransferase / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D012307:Risk Factors
chemical_list: C494489:PEMT protein, human; D050918:Phosphatidylethanolamine N-Methyltransferase