title: The O blood group protects against venous thromboembolism in individuals with the factor V Leiden but not the prothrombin (factor II G20210A) mutation.
abstract: We investigated the influence of the ABO blood group in the observed prevalences of the recently described factor V R506Q and factor II G20210A mutations in a thrombotic population. We determined the ABO blood group in a sample of 178 unselected patients (aged 17-83 years), diagnosed at our center with deep vein thrombosis or pulmonary embolism. The results of this study show a high prevalence of thrombosis in the non-O blood group. In the general population, the prevalence as a fraction of the O blood group was 2.69 (confidence interval 1.90-3.82). Of the factor V R506Q carriers (n = 28), only one had O group blood and 27 of 28 were non-O (24 A, one B and two AB). However, within the group of factor II G20210A carriers (n = 17), seven had O, nine A and one B type blood. The prevalence of the factor V R506Q mutation within the O blood group was 2.4% (one of 42), significantly lower than in the A group (23.3%, 24 of 103; P = 0.002), or in the overall non-O group (19.9%, 27 of 136; P = 0.006). This prevalence was similar to that observed previously in the non-thrombotic population in our area (3.5%; P = 0.9). We analyzed the clotting activity of factor VIII and we found higher levels in the non-O group (1.78+/-0.61 U/ml) than in the O blood group (1.30+/-0.51 U/ ml; P < 0.0001). We speculate that factor Va in individuals with the factor V Leiden mutation could interact with the high levels of factor VIII clotting activity as a necessary cofactor.
authors.affiliation: Hematology Department, Hospital S. Agustín, Avilés, Spain. jagonzalez@medynet.com
authors.forename: A J
authors.initials: AJ
authors.lastname: González Ordóñez
authors.forename: J M
authors.initials: JM
authors.lastname: Medina Rodriguez
authors.forename: L
authors.initials: L
authors.lastname: Martín
authors.forename: V
authors.initials: V
authors.lastname: Alvarez
authors.forename: E
authors.initials: E
authors.lastname: Coto
mesh_terms: D000017:ABO Blood-Group System; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005165:Factor V / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011516:Prothrombin / Q000235:genetics*; D011655:Pulmonary Embolism / Q000097:blood* / Q000235:genetics*; D013924:Thrombophlebitis / Q000097:blood* / Q000235:genetics*
chemical_list: D000017:ABO Blood-Group System; C095381:factor V Leiden; D005165:Factor V; D011516:Prothrombin