title: Thermolabile methylenetetrahydrofolate reductase enzyme genotype is frequent in type 2 diabetic patients with normal fasting homocysteine levels.
abstract: OBJECTIVE
  To investigate the plasma homocysteine concentrations with regard to nutritional, metabolic and genetic factors and to find out the frequency and impact of thermolabile methylenetetrahydrofolate reductase (T-MTHFR) polymorphism in patients with type 2 diabetes mellitus.
  
  
  METHODS
  A cross-sectional study.
  
  
  METHODS
  A total of 94 subjects with type 2 diabetes mellitus and 91 healthy age- and sex-matched nonsmoking volunteers were recruited.
  
  
  METHODS
  Age, sex, duration and complications of diabetes mellitus, metabolic variables, fasting plasma homocysteine levels, and presence of T-MTHFR polymorphism were evaluated for all participants. Presence of T-MTHFR polymorphism was analysed to define any possible role in diabetes progress, complications and metabolic milieu.
  
  
  RESULTS
  Fasting homocysteine levels were similar in diabetic patients and controls. Prevalence of homozygous polymorphism of thermolabile MTHFR gene (TT) was encountered more frequently in patients with diabetes mellitus than the healthy controls (P = 0.004). Subgrouping of the patients with respect to MTHFR genotype revealed similar metabolic variables and frequency of chronic complications of diabetes mellitus in groups. Patients with TT genotype revealed longer diabetes duration when compared with the patients having heterozygous mutation of thermolabile MTHFR or normal homozygous MTHFR genotypes (P = 0.046).
  
  
  CONCLUSIONS
  Type 2 diabetic patients have similar fasting plasma homocysteine levels with that of age- and sex-matched healthy people. There is no correlation between diabetic complications and this amino acid metabolite. On the contrary, thermolabile variant of MTHFR genotype is found to be more frequent in diabetic patients especially in those who have experienced a longer duration of disease.
authors.affiliation: Department of Endocrinology and Metabolism, Baskent University Faculty of Medicine, Turkey. tt04-k@tr.net <tt04-k@tr.net>
authors.forename: N B
authors.initials: NB
authors.lastname: Tutuncu
authors.forename: T
authors.initials: T
authors.lastname: Erbas
authors.forename: M
authors.initials: M
authors.lastname: Alikasifoglu
authors.forename: E
authors.initials: E
authors.lastname: Tuncbilek
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000201:enzymology / Q000235:genetics*; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D020022:Genetic Predisposition to Disease; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic
chemical_list: D006710:Homocysteine; D042965:Methylenetetrahydrofolate Reductase (NADPH2)