title: [Homocysteine levels and polymorphisms of MTHFR and CBS genes in Colombian patients with superficial and deep venous thrombosis].
abstract: BACKGROUND
  Thrombosis develops when the hemostatic system is incorrectly activated due to the unbalance between procoagulant, anticoagulant and fibrinolytic mechanisms allowing the formation of a clot within a blood vessel. The risk factors of this pathology can be acquired or can be genetic.
  
  
  OBJECTIVE
  To analyze in a Colombian population with diagnosis of venous thrombosis, lipid profile, glucose and homocystein levels, to calculate the alleles and genotypic frequencies of polymorphisms c.699 C>T, c.1080 C>T, c.844ins68 of the cystathionine ß synthase and the c.677 C>T of the methylenetetrahydrofolate reductase (MTHFR) genes.
  
  
  METHODS
  Thirty three patients and their controls were studied. The biochemical test was carried out by colorimetric methods and immunoassay. In this survey we used the restriction fragments longitude polymorphism (RLFP) technique to identify the polymorphisms mentioned. The association study was performed through the chi square test.
  
  
  RESULTS
  We confirmed that gene alterations increase risk for pathology; we found statistically significant differences in the group with hypercholesterolemia in presence of the polymorphism c.699 C>T in the CBS gene, showing a protective effect in the individuals carrying this genetic variation. Likewise, we found a statistical trend for an eventual protective effect of the CBS c.844ins68 polymorphism to venous thrombotic disease.
  
  
  CONCLUSIONS
  There were not any statistically significant differences in homocystein levels between cases and controls; nevertheless, the variability in the plasma concentrations was greater in the group of cases.
authors.affiliation: Instituto de Genética Humana, Pontificia Universidad Javeriana, Bogotá, DC, Colombia.
authors.forename: Claudia
authors.initials: C
authors.lastname: Ayala
authors.forename: Reggie
authors.initials: R
authors.lastname: García
authors.forename: Edith
authors.initials: E
authors.lastname: Cruz
authors.forename: Karol
authors.initials: K
authors.lastname: Prieto
authors.forename: Marta
authors.initials: M
authors.lastname: Bermúdez
mesh_terms: D016022:Case-Control Studies; D003105:Colombia; D003541:Cystathionine beta-Synthase / Q000235:genetics*; D005260:Female; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D008875:Middle Aged; D011110:Polymorphism, Genetic; D020246:Venous Thrombosis / Q000097:blood* / Q000235:genetics*
chemical_list: D006710:Homocysteine; D042965:Methylenetetrahydrofolate Reductase (NADPH2); D003541:Cystathionine beta-Synthase