title: Genetic association between methylenetetrahydrofolate reductase gene polymorphism and risk of osteonecrosis of the femoral head.
abstract: BACKGROUND
  Methylenetetrahydrofolate reductase (MTHFR) SNP rs1801133 has been frequently investigated in recent years. Relevant candidate gene association studies with this SNP and osteonecrosis of the femoral head (ONFH) reported conflicting results. Meta-analysis provides a method to combine these data and to determine the association in a larger sample size.
  
  
  METHODS
  We conducted a systematic search to identify possible studies. Four pooled ORs (odds ratios, T versus C, TT versus CC, TT/CT versus CC, and TT versus CT/CC), along with 95% confidence interval (CI), were calculated to evaluate the association between SNP rs1801133 and ONFH susceptibility. Both fixed effects model and random effects model were used.
  
  
  RESULTS
  We eventually included twelve studies in this analysis, with results showing no overall association between ONFH susceptibility and SNP rs1801133 (T versus C: OR=1.15, 95% CI=0.97-1.38; TT versus CC: OR=1.15, 95% CI=0.91-1.46; TT/CT versus CC: OR=1.09, 95% CI=0.95-1.25; and TT versus
  OR=1.16, 95% CI=0.93-1.45). When stratified based on ethnicity, the results were still not significant.
  
  
  CONCLUSIONS
  Our findings are generally supportive of no association between MTHFR SNP rs1801133 and the etiology of ONFH.
authors: Department of Orthopaedics, Chinese People's Liberation Army General Hospital, 301 Orthopaedic Hospital, 28 Fuxing Road, Haidian District, Beijing 100853, China.
authors: Wei
authors: W
authors: Chai
authors: Department of Orthopaedics, Chinese People's Liberation Army General Hospital, 301 Orthopaedic Hospital, 28 Fuxing Road, Haidian District, Beijing 100853, China.
authors: Zhendong
authors: Z
authors: Zhang
authors: Department of Orthopaedics, Chinese People's Liberation Army General Hospital, 301 Orthopaedic Hospital, 28 Fuxing Road, Haidian District, Beijing 100853, China.
authors: Ming
authors: M
authors: Ni
authors: Cancer Center, Division of Internal Medicine, Chinese PLA General Hospital & Chinese PLA Medical School, 28 Fuxing Road, Haidian District, Beijing 100853, China.
authors: Peiliang
authors: P
authors: Geng
authors: Medical School of Nankai University, 94 Weijin Road, Tianjin 300071, China.
authors: Zijian
authors: Z
authors: Lian
authors: Department of Orthopaedics, Chinese People's Liberation Army General Hospital, 301 Orthopaedic Hospital, 28 Fuxing Road, Haidian District, Beijing 100853, China.
authors: Guoqiang
authors: G
authors: Zhang
authors: Department of Orthopaedics, University of Chicago Hospital, 5841 S. Maryland Avenue, Chicago, IL 60637, USA.
authors: Lewis L
authors: LL
authors: Shi
authors: Department of Orthopaedics, Chinese People's Liberation Army General Hospital, 301 Orthopaedic Hospital, 28 Fuxing Road, Haidian District, Beijing 100853, China.
authors: Jiying
authors: J
authors: Chen
mesh_terms: D005271:Femur Head Necrosis / Q000235:genetics*; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*
chemical_list: D042965:Methylenetetrahydrofolate Reductase (NADPH2)