Factor V1691 G-A, prothrombin 20210 G-A, and methylenetetrahydrofolate reductase 677 C-T variants in Turkish children with cerebral infarct

Inherited gene defects related to the coagulation system have been reported as risk factors for ischemic stroke. These gene defects include a G-A tran sition at nucleotide 1691 in exon 10 of the Factor V gene causing activated protein C resistance; a G-A transition in the 3' untranslated region of th e prothrombin gene at nucleotide position 20210 (G-A), which is associated with increased levels of prothrombin activity; and a C-T polymorphism at nu cleotide 677 in the methylenetetrahydrofolate reductase gene responsible fo r an alanine to valine substitution, resulting in the synthesis of a thermo labile form of methylenetetrahydrofolate reductase that causes increased le vels of homocysteine. The case-control study included 28 patients with cere bral infarction; all were 18 years of age or younger (range, 10 months to 1 8 years). Seven (25%) of the 28 patients were heterozygous for the FV1691 m utation. Five (17.8%) of the patients carried the PT 20210A mutation. Two ( 7.1%) of the patients carried both mutations. When compared to controls, th e difference was significant for both mutations (P = .007;.04). The frequen cy of allele T of methylenetetrahydrofolate reductase 677 was 0.3214, which was not significant when compared to controls (0.231; P = .3:). A total of 12 (42.8%) patients carried one or both of the mutations FV1691 G-A and PT 20210 G-A. From our data, it appears that FV1691 G-A and PT20210 G-A are as sociated with cerebral infarct risk independently. Risk assessment of doubl e prothrombotic gene alterations did not reveal synergy between these mutat ions. In conclusion, the presence of FV1691 A and PT20210 A mutations but n ot the methylenetetrahydrofolate reductase 677 TT mutation correlate with t he occurrence of cerebral infarction in children.