Correspondence to:

www.cmj.hr Aim To determine the differences in plasma homocysteine levels between three MTHFR 677 genotype subgroups in patients with thrombosis and in controls, as well as be-tween patients with thrombosis and controls with the same MTHFR 677 genotype. Methods This case-control study was conducted in Clin-ical Center of Vojvodina, Novi Sad, from June to Decem-ber 2011. We included 65 patients with either arterial or venous thrombosis (mean age, 40.97 ± 11.38 years) and 65 controls with no history or clinical evidence of any throm-botic event (mean age, 41.23 ± 11.12 years). Patients and controls were age- and sex-matched. Results In comparison with controls, thrombotic patients had significantly higher homocysteine levels (12.81 ± 4.9