MTHFR and Rare hereditary thrombophilia: In addition, the presence of inherited thrombophilia in 100 Colombian patients with deep venous thrombosis and in a control group (n = 114) was evaluated with the following results in patients versus controls: 10% versus 0.9% were heterozygous for FV Leiden, 3% versus 0% were heterozygous for FII G20210A (one patient was homozygous), 24% versus 19.3% were homozygous for MTHFR 677T, and 25.2% versus 5.3% had APC resistance (these thrombophilias reached statistical significance, except for the MTHFR polymorphisms) [37].