PROS1 and hereditary antithrombin deficiency: Positive genetic results for other congenital thrombophilia mutations were identified, as well: Factor V Leiden, Prothrombin G20210A, Factor XIII (Val34Leu), Fibrinogen 455 G>A, GP IIb/IIIa L33P and Factor V A4070G (HR2 haplotype) heterozygosity, PAI-1 4G/5G promoter variants, and activated protein C resistance V. In addition, 28 patients had associated protein S, protein C, or antithrombin deficiency.