In the normal person, factor V functions as a cofactor to allow factor Xa to activate prothrombin, resulting in the enzyme thrombin.
(Together with the general lack of nomenclature standard, this variance means that the SNP can be referred to in several ways, such as G1691A, c.1691G>A, 1691G>A, c.1746G>A, p.Arg534Gln, Arg506Gln, R506Q or rs6025.)