Factor V Leiden (R506Q), Prothrombin G20210A, and MTHFR C677T Variants and Thrombophilia in Qatar Biobank Participants: A Case Control Study

<b>Background:</b> Thrombophilia, a predisposition to develop blood clots, is very common and can have serious sequelae. <b>Aim:</b> This study aimed to determine the prevalence of three thrombophilia-related genetic variants-factor V Leiden (FVL), prothrombin (F2) G20210A, and MTHFR C677T-in the Qatari population and their associations with self-reported thrombosis. <b>Methods:</b> We analysed samples from 408 Qatari participants [304 controls and 104 with self-reported thrombosis (deep vein thrombosis, pulmonary embolus, or ischaemic stroke)] from the Qatar Biobank. FVL (rs6025), F2 (rs1799963), and MTHFR (rs1801133) variants were genotyped using TaqMan assays. <b>Results:</b> Participants with self-reported thrombosis were older and more likely to be female. FVL A allele carriage (GA + AA vs. GG) was significantly higher in thrombosis cases (OR 3.6, <i>p</i> = 0.0002). In addition, individuals carrying FVL AA and GA genotypes had a lower mean platelet volume on average than those with the GG genotype (<i>p</i> = 0.03). MTHFR C677T did not show a similar association, and the F2 G20210A variant was too rare for analysis. <b>Conclusions:</b> There were significant differences in FVL A allele carriage between individuals with a history of thrombosis and the control group. Future research should explore the complex interplay between genetics and environment in thrombosis risk within this population.