A recently identified gene may help clinicians fine-tune warfarin doses more quickly and precisely, according to a new study. Because warfarin has a narrow therapeutic window, many patients must undergo months of titration to achieve their ideal dosage.
Researchers believe that variations in the gene encoding vitamin K epoxide reductase complex 1 (VKORC1) explain why appropriate warfarin doses vary widely among patients. They found that Asian-Americans were more likely to have the low-dose VKORC1 gene, European Americans the intermediate-dose gene, and African-Americans the high-dose gene. Screening for VKORC1 variations could help improve warfarin dosing, but the researchers say more studies are needed first.
Effect of VKORC1 haplotypes on transcriptional regulation and warfarin dose, The New England Journal of Medicine, MJ Rieder, et al., June 2, 2005.