Venous thrombosis in relation to fibrinogen and factor VII genes among African-Americans

We evaluated the relation between venous thrombosis and plasma fibrinogen l evels, the HaeIII and BcI polymorphisms of the beta fibrinogen gene, and th e MspI polymorphisms of the factor VII gene in a case-control study of Afri can-Americans. The study included 91 venous thrombosis cases and 185 contro l subjects obtained from a hospital in Atlanta, Georgia. High plasma fibrin ogen was associated with increased risk of venous thrombosis, but the findi ng was not statistically significant. There was little association between the HaeIII polymorphisms and the BclI polymorphisms and the risk of venous thrombosis. The prevalence of the M2/M2 genotype of the factor VII gene was higher among cases than controls, but the difference was not statistically significant. The prevalence of the HaeIII H2 allele and the BclI B2 allele of the beta fibrinogen gene, both of which have been associated with sligh tly higher levels of plasma fibrinogen in most studies, is considerably low er among African-Americans in this study than it is among Whites in the Uni ted States and among Northern Europeans. The study is limited by its small size. However, despite this limitation, it supports the belief that increas ed plasma fibrinogen levels are associated with increased venous thrombosis risk. The study also indicated that the HaeIII and the BclI polymorphisms of the beta fibrinogen gene and the MspI polymorphisms of the factor VII ge ne are not strong determinants of venous thrombosis. (C) 2000 Elsevier Scie nce Inc. All rights reserved.