Now that the human genome has been mapped, genetic markers have been used to identify links to major disease. Swedish researchers have taken this one step further by identifying a large selection of genetic markers (326,000) and finding the correlation between their presence and the suitable dosages of Warfarin.
The drug Warfarin is used to thin the blood and prevent blood clotting in patients who have a high likelihood of suffering from deep vein thrombosis, stroke and heart attack. The risk amongst patients, however, varies and so each individual will require a different dosage. This can vary by as much as two hundred times the concentration of the minimum dosage. Due to the broad range of concentrations, current methods cannot be used to precisely determine the correct prescription for each patient, but rather a range of suitable options.
Incorrect doses of Warfarin can lead to the blood being thinned too much causing bleeding or leave the blood in a thickened state that will still present a high risk factor for the consequences the drug wishes to prevent. As many as, “70 to 100 severe bleeding events occur each year for every 1000 patients treated with Warfarin,” (Higashi, M. et. al, 2002)
The genes VKORC1, CYP2C9 and CYP4F2 have been identified by researchers as having a strong correlation with the dosage of Warfarin required. By determining the variants in these genes a correct dosage can be determined.
This leads the way into research that will result in prescriptions that can be tailor made to suit your genetic makeup. This will take the uncertainty out of deciding dosages and result in safer medical treatments.
Takeuchi F, McGinnis R, Bourgeois S, Barnes C, Eriksson N, et al. (2009) "A Genome-Wide Association Study Confirms VKORC1, CYP2C9, and CYP4F2 as Principal Genetic Determinants of Warfarin Dose." http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1000433
Via http://www.medicalnewstoday.com/articles/143100.php
