F2 and essential thrombocythemia: On the contrary, no significant statistical difference in the percentage of factor V Leiden, prothrombin gene, and MTHFR mutations in ET patients with JAK2 V617F positive mutation versus the JAK2 V617F negative group (P > 0.05) (Table 4) and Percentage of factor V Leiden, prothrombin gene, and MTHFR mutations in patients with cardiovascular risk factors versus the patients with noncardiovascular risk factors group (P > 0.05) (Table 5).