An age-related decrease in factor V Leiden frequency among Polish subjects

Allele frequency distribution of 1691G >A F5 (which confers Factor V Leiden) across Europe, including Slavic populations

The allele 1691A F5, conferring Factor V Leiden, is a common risk factor in venous thromboembolism. The frequency distribution for this allele in Western Europe has been well documented; but here data from Central, Eastern and South-Eastern Europe has been included. In order to assess the significance of the collated data, a chi-squared test was applied, and Tukey tests and z-tests with Bonferroni correction were compared. Results: A distribution with a North-Southeast band of high frequency of the 1691A F5 allele was discovered with a pocket including some Southern Slavic populations with low frequency. European countries/regions can be arbitrarily delimited into low (group 1, <2.8 %, mean 1.9 % 1691A F5 allele) or high (group 2, ≥2.8 %, mean 4.0 %) frequency groups, with many significant differences between groups, but only one intra-group difference (the Tukey test is suggested to be superior to the z-tests). Conclusion: In Europe a North-Southeast band of 1691A F5 high frequency has been found, clarified by inclusion of data from Central, Eastern and South-Eastern Europe, which surrounds a pocket of low frequency in the Balkans which could possibly be explained by Slavic migration. There seem to be no indications of variation in environmental selection due to geographical location.

The frequencies of six important thrombophilic mutations in a population of the Czech Republic

The primary aim was to determine frequencies of mutations related to risk of venous thrombosis in healthy Caucasians in Central Bohemia. In a cohort of 1527 healthy individuals the frequency of risk alleles for the mutations FV Leiden and FII 20210G>A was 4.5% and 1.3%, respectively. Frequency of 4G PAI-1 allele was 55.5%. Genotype frequencies were: GG 91.03%, GA 8.91%, and AA 0.07% for FV Leiden; GG 97.45%, GA 2.49%, and AA 0.07% for FII 20210G>A; 4G/4G 30.26%, 4G/5G 50.56%, and 5G/5G 19.19% for PAI-1. Frequency of the risk allele A in polymorphism SERPINC1 (IVS +141G >A) was 11.3%, and frequencies of genotypes were as follows: GG 78.36%, GA 20.66%, and AA 0.98%. Frequency of the risk allele T for polymorphism GP6 13254T>C was 87.7%, and frequencies of genotypes were as follows: TT 77.14%, TC 21.15%, and CC 1.70%. Frequency of the risk allele A in polymorphism CYP4V2 (Lys259Gln) was 65.2%, and frequencies of genotypes were: CC 12.25%, CA 45.12 %, and AA 42.63%. All observed genotypes and alleles frequencies were without gender differences. Their occurrences confirm a relatively high prevalence of hereditary thrombophilia predisposition in the Czech Republic.

Prevalence of 1691G>A FV mutation in Poland compared with that in other Central, Eastern and South-Eastern European countries

The 1691G>A FV variant has been described as a common genetic risk factor in venous thromboembolism. The purpose of this study was to provide a further frequency value for 1691G>A FV in Poland and to collate summary data from Central (Poland, Czech, Slovakia), Eastern (Russia, Belarus, Ukraine) and South-Eastern (Slovenia, Croatia, Bosnia and Herzegovina, Serbia, Montenegro, Macedonia, Bulgaria) European countries. For this purpose in 2007 the 1691G>A FV variant was analyzed by polymerase chain reaction-restriction fragment length polymorphism from DNA collected in 2005-2006. We studied 650 subjects: 400 newborns and 250 older individuals (mean age 46.1 y) from Poland and compared results with reports from other countries, as well as with the frequency trend of 845G>A HFE across South-Eastern European countries using centroid cities. From our 1691G>A FV study we identified 626 GG homozygotes, 23 GA heterozygotes, and 1 AA homozygote (n = 650), giving an A allele frequency of 1.9%, and a summed frequency value for Poland of 2.0% (n = 1588); the frequency in Central European countries was 3.9% (n = 4559), mostly due to the high value in the Czech Republic: 5.1% (n = 2819); the South-Eastern European countries had 2.5% (n = 2410). Among the Eastern European countries the 1691G>A FV allele frequency was 1.9% (n=791), between the South-Eastern and Eastern European countries there was no significant difference (p=0.17). We confirm that the 1691G>A FV allele frequency in Poland, as well as other countries compared, is significantly lower than that in Czech.