Effect of metylenetetrahydrofolate reductase 677 C-T, 1298 A-C, and 1317 T-C on factor V 1691 mutation in Turkish deep vein thrombosis patients

Possible effect of three common mutations in (MTHFR 677 C-T; 1317 T-C; 1298 C-A:) and FV 1691 G-A mutation was studied in Turkish patients with thromb osis and compared with normal controls. The case-control study included 68 patients with the diagnosis of deep vein thrombosis and 66 controls, consec utively selected among subjects without personal and familial history of at herothrombosis. Patients with deep vein thrombosis were selected if Doppler ultrasonography was positive. Only, the comparision of factor V 1691 G-A m utation revealed statistically significant difference in control (6.06%) an d deep vein thrombosis (23.5%) group. Risk assessment of double prothrombot ic gene alterations revealed only FV 1691 G-A mutation as an independent ri sk factor for thrombosis (odds ratio 4.7 [1.5-15.0]), but our data suggeste d that MTHFR 677 has effect on its own (odds ratio 1.97 [0.6-2.7]) but may have synergy with FV 1691 G-A (odds ratio 8.12 [2.0-25.3]). However, MTHFR 1298 A-C and 1317 T-C does not have any effect; furthermore, being heterozy gote at two different loci or homozygosity at least in a locus for 677 and 1298 revealed a significant increase (odds ratio 9 and 24 [1.3-59.3 and 2.3 -240.3]) between these two groups. (C) 2000 Elsevier Science Ltd. All right s reserved.