F5 and Stroke: Several meta-analysis studies have proposed that the factor V Leiden (F5 rs6025) and the prothrombin gene G20210A (F2 rs1799963) polymorphisms are weak risk factors for CAD and stroke, particularly among younger patients and women. 3, 29, 30  In a recent comprehensive meta-analysis, the G20210A variant was associated with a significantly increased risk for CAD in Europeans but not in Americans or Asians.   3  Moreover, the only large prospective cohort study published to date failed to establish any link between the G20210A polymorphism and myocardial infarction or stroke.   3 1