Test Details: This test primarily detects common genetic variations in two genes, CYP2C9 and VKORC1. A healthcare practitioner orders this test to help select appropriate doses of warfarin and/or to achieve appropriate dose levels more quickly. Genetic testing for warfarin sensitivity may help to shorten the time it takes to reach a stable dose; that is, to achieve adequate "blood-thinning" without bleeding episodes. Most often, it is observed that people more sensitive to warfarin need smaller doses; however, people who are less sensitive may need larger doses.