Genetic risk factors for venous thrombosis include two relatively common mutations: R506Q in exon 10 of the human Factor V gene (known as the Factor V Leiden mutation) and G20210A in the 3' untranslated region of the Prothrombin gene. Testing for the presence these mutations is becoming increasingly important in the diagnostic evaluation of a range of different individuals in addition to those already presenting with hypercoagulability or other symptoms of venous thrombosis (see references below, with links to abstracts). Screening for a third, rarer mutation (known as the Factor V Cambridge mutation), is also possible. This may be appropriate for patients with known APC resistance who are also negative for either of the above two mutations.

1) Air travel and thrombosis. Giangrande PL.Int J Clin Pract 2001 Dec;55(10):690-3

2) Factor V Leiden and G20210A Prothrombin mutations are risk factors for very early recurrent miscarriage. Reznikoff-Etievan MF, Cayol V, Carbonne B, Robert A, Coulet F, Milliez J. BJOG 2001 Dec;108(12):1251-4

3) Combined effect of Factor V Leiden and Prothrombin 20210A on the risk of venous thromboembolism: Pooled analysis of 8 case-control studies including 2310 cases and 3204 controls. Study Group for Pooled-Analysis in Venous Thromboembolism. Emmerich J, Rosendaal FR, Cattaneo M, Margaglione M, De Stefano V, Cumming T, Arruda V, Hillarp A, Reny JL. Thromb Haemost 2001 Sep;86(3):809-16

4) Association of factor V Leiden mutation with delayed graft function, acute rejection episodes and long-term graft dysfunction in kidney transplant recipients. Hocher B, Slowinski T, Hauser I, Vetter B, Fritschel L, Bachert D, Kulozik A, Neumayer HH. Thromb Haemost 2002 Feb;87(2):194-8

The cost of this assay is £50 per sample, for both the Factor V Leiden and Prothrombin G20210A mutations combined. The Factor V Cambridge mutation alone costs a further £50. Either whole blood or cheek swab specimens can be accepted. (Please enquire for bulk or contract discounts).