A common genetic variation that can impact the therapeutic dose of the blood-thinning drug warfarin among African Americans has been found

The finding revealed that people of African ancestry who have the rs12777823 variant require a notably lower dose of warfarin to achieve all the advantages, compared to those without this single-nucleotide polymorphism (SNP). Adding this genetic marker - found in more than 40% of African American patients in the study - to standard dosing algorithms improved the predictability of warfarin dosing by 21% in these individuals, which has the potential to increase the safety and effectiveness of this notoriously hard to dose drug. Previous research has revealed that two genes, VKORC1 and CYP2CP, can account for about 30% of the difference in warfarin response in people of Asian and European descent. However, these genetic markers are less predictive of dosing regimens in African Americans.