Factor V Leiden (Arg506Gln), a confounding genetic risk factor but not mandatory for the occurrence of venous thromboembolism in homozygotes and obligate heterozygotes for Cystathionine β-synthase deficiency - Yap, S; O’Donnell, KA; Neil, CO; Mayne, PD; Thornton, P; Naughten, E (Thromb Haemost, 1999)