title: Prevalence of factor V Leiden and prothrombin G20210A mutation in a large French population selected for nonthrombotic history: geographical and age distribution.
abstract: Among inherited risk factors for venous thrombosis, the most common are the FV-G1691A and FII-G20210A polymorphisms. The FV-G1691A polymorphism is preferentially observed in Europe, with differences between European countries. The FII-G20210A polymorphism is observed all over the world. The study was designed to compare the prevalence of the FV-G1691A and FII-G20210A polymorphisms in a large French population of unrelated individuals with no thrombotic disease history and to determine the age and geographical distributions. Over a period of 18 months, 6154 individuals were included throughout France and FV-G1691A and FII-G20210A polymorphisms were determined. The FV-G1691A prevalence was 3.84% (95% confidence interval 3.35-4.33) and the FII-G20210A prevalence was 3.07% (95% CI 2.63-3.51). A north-east/south-west gradient was observed in the FV-G1691A geographical distribution. No difference was observed in the geographical distribution of FII-G20210A polymorphism nor in the age distribution of the two polymorphisms. The prevalence of the two polymorphisms was similar whatever the blood group (O or non-O). Plasma D-dimers were significantly higher in healthy individuals with FV-G1691A but not in individuals with FII-G20210A. Thirty percent of variation in plasma prothrombin level was explained by environmental factors (serum cholesterol, age, oral contraception, hormonal replacement therapy, body mass index, sex) and genetic factors (FII-G20210A). As expected, individuals with FII-G20210A displayed higher plasma prothrombin level compared with individuals with wild type. However, this was not associated with a modification of the fibrin clot elastic modulus. This study shows a differential distribution of the two polymorphisms among the French territory. These polymorphisms confer a very mild hypercoagulable state as shown by the limited increased in basal D-dimers in mutated FV-G1691A populations and only a trend that does not reach statistical significance for FII-G20210A population.
authors.affiliation: Hématologie Biologique, Hôpital Lariboisière, Paris, France. elisabeth.mazoyer@avc.aphp.fr
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Mazoyer
authors.forename: Laurent
authors.initials: L
authors.lastname: Ripoll
authors.forename: René
authors.initials: R
authors.lastname: Gueguen
authors.forename: Laurence
authors.initials: L
authors.lastname: Tiret
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Collet
authors.forename: Claire Bal
authors.initials: CB
authors.lastname: dit Sollier
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Roussi
authors.forename: Ludovic
authors.initials: L
authors.lastname: Drouet
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004252:DNA Mutational Analysis; D005165:Factor V / Q000032:analysis*; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis; D005602:France / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D017354:Point Mutation; D044382:Population Groups / Q000235:genetics*; D015995:Prevalence; D011516:Prothrombin / Q000032:analysis / Q000235:genetics*; D012307:Risk Factors; D019371:Topography, Medical; D020246:Venous Thrombosis / Q000235:genetics; D055815:Young Adult
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; C095381:factor V Leiden; C036309:fibrin fragment D; D005165:Factor V; D011516:Prothrombin