Relationship between polymorphisms in thrombophilic genes and preeclampsia in a Brazilian population.

The purpose of this study was to evaluate the thrombophilic genes in pregnant women with and without preeclampsia independently or in combination. In a prospective case-control study, we investigated four polymorphisms in thrombophilic genes in 75 women with mild or severe preeclampsia and 145 women with normal pregnancy. The genotype frequencies were assessed and the odds ratio (OR) calculated. When we analyzed the polymorphisms independently and the development of preeclampsia, no association was observed [methylenetetrahydrofolate reductase (MTHFR) 677TT genotype, OR 2.07, 95% confidence interval (CI) 0.99-4.30; prothrombin mutation (F II) (GA or AA genotypes) OR 8.11, 95% CI 0.89-73.92; factor V Leiden (FV Leiden) OR 3.94, 95% CI 0.35-44.23; plasminogen activator inhibitor (PAI-1) 4G/4G genotype, OR 1.63, 95% CI 0.87-3.05] not even with severe preeclampsia subgroup analysis. However, when we investigated a possible interaction among these polymorphisms on the development of the preeclampsia, the OR for having one risk genotype, one or two genotype risk factors and two genotype risk factors compared to those without genotype risk factors were 1.97 (95% CI 1.08-3.59), 2.21 (95% CI 1.25-3.92) and 4.27 (95% CI 1.3-13.9), respectively. In conclusion, in the population analyzed, the presence of the genotype risk factors alone does not seem to be associated with the development of preeclampsia even in the severe presentation form. However, an interaction among the MTHFR, F II, FV and PAI-1 gene polymorphisms on the development of the preeclampsia was indicated.