Moreover, individuals who carry the mutation can pass it on to their offspring.The mutation increases the risk of developing deep vein thrombosis (DVT), which can cause pain and swelling, and sometimes post-thrombotic syndrome, ulcers, or pulmonary embolism. Most individuals do not require treatment but do need to be cautious during periods when the possibility of blood clotting are increased; for example, during pregnancy, after surgery, or during long flights. Occasionally, blood-thinning medication may be indicated to reduce the risk of clotting.Heterozygous carriers who take combined birth control pills are at a 15-fold increased risk of VTE, while carriers also heterozygous with factor V Leiden have an approximate 20-fold higher risk. In a recommendation statement on VTE, genetic testing for G20210A in adults that developed unprovoked VTE was disadvised, as was testing in asymptomatic family members related to G20210A carriers who developed VTE. In those who develop VTE, the results of thrombophilia tests (wherein the variant can be detected) rarely play a role in the length of treatment. Cause
The polymorphism is located in a noncoding region of the prothrombin gene (3 untranslated region nucleotide 20210), replacing guanine with adenine. The position is at or near where the pre-mRNA will have the poly-A tail attached.
Terminology
Because prothrombin is also known as factor II, the mutation is also sometimes referred to as the factor II mutation or simply the prothrombin mutation; in either case, the names may appear with or without the accompanying G20210A location specifier (unhelpfully, since prothrombin mutations other than G20210A are known). Notes
References
External links

Mannucci, P. M. & Franchini, M. (2015). "Classic thrombophilic gene variants". Thrombosis and Haemostasis. 114 (5): 885–889. doi:10.1160/th15-02-0141. PMID 26018405. Archived from the original (review) on 10 June 2016. Retrieved 21 May 2016.