Primary DVT is a serious, potentially fatal disease that may affect genetically predisposed individuals. MTHFR gene mutation has been identified as risk factor for venous thrombosis in several studies due to the associated mild Homocystenemia. The mutation is due to a C T substitution at position 677 in the MTHFR gene. The study underhand has revealed that there is a statistically significant relationship between MTHFR gene mutation and incidence of DVT with a relative risk of 1.5. The results also revealed a higher incidence of Proximal DVT in patients with MTHFR gene mutation as opposed to distal DVT.