Here, we analysed 58 individuals with genetic predisposition to thrombosis defined by at least one variation in F5 or F2 genes and one in MTHFR. The results obtained show that approximately 60.3% present the genotype CYP2C9*1/*1, while the remaining have CYP2C9*2 and CYP2C9*3 variants. This evidence concerns the gene MTHFR and Venous thrombosis.