CYP2C9 polymorphism studies in the Saudi population

To determine the prevalence of CYP2C9 polymorphism in normal Saudis [controls], in Saudi patients with venous thrombosis, in patients requiring low dose warfarin [study group] for anticoagulation, and to compare our results to those from other populations. Blood from the "control and study" groups was collected from November 2001 to November 2008. The DNA was extracted, stored at -70°C and later tested for the CYP2C9 polymorphism using established methods. Clinical data were collected through direct interview, chart review, and the Saudi Thrombosis and Familial Thrombophilia Registry. All individuals consented. The prevalence of CYP2C9 polymorphisms in the Saudi population was similar to Caucasians and higher than Asian and African. The control [n=670] and patients with venous thrombosis [n=110] groups showed similar prevalence of the normal wild type CYP2C9 and the 2 polymorphisms tested [CYP2C9*2 and CYP2C9*3]. The group that required low dose warfarin [n=25] showed significantly higher CYP2C9 polymorphism, required 40% less warfarin and had a higher rate of bleeding [5% versus 1.8%]. The prevalence of the abnormal polymorphism in the Saudi population of 35.5% is similar to that in Caucasians. Patients with the CYP2C9 polymorphism required 40% less warfarin and had more serious bleeds

Saudi thrombosis and familial thrombophilia registry Design, rational, and preliminary results

To describe the Registry and report preliminary data for the prevalence of 5 prothrombotic gene mutations in the normal Saudi population. Blood from consenting healthy Saudi individuals and patients with venous thrombosis [VT] from different regions of the Kingdom was collected from November 2001 until July 2007. The extracted DNA of each sample was kept at -70°C until tested for 5 known prothrombotic factors using established methods. Only patients with confirmed VT were included. Data generated through direct interview were entered into the Saudi Thrombosis and Familial Thrombophilia [S-TAFT] Register. The consent and demographic data collection forms and the S-TAFT Register were developed using the SQL web based software. Nine hundred and two DNA samples of consenting healthy Saudi individuals were tested for factor V Leiden [FVL], prothrombin [PT] 20210 G>A, 5-10 methylenetetrahydrofolate reductase [MTHFR] 677 C>T, the 4G/5G polymorphism of Plasminogen activator inhibitor type 1 [PAI-1 4G/5G], and factor V HR2 [FVHR2] haplotype. The incidence of FVL among healthy subjects was 1.3%, PT 20210 G>A 0.7%, homozygous MTHFR 677C>T 2.45%, PAI 4G/4G 10.1%, and FVHR2 26.1%. Our preliminary data from healthy Saudi individuals suggest that the incidence of the 5 prothrombotic risk factors is lower than in most other populations, except for FVHR2