The subject has been brought up, and there's research showing that Asians (if I remember correctly) are more sensitive to warfarin than caucasians. There may be a response to coumadin that is related to ethnic group or some genetic markers. I've read that it's used to predict a starting dose for anticoagulation therapy. I didn't read your link to a research project, but I suspect that the testing can 'probably' be done on those about to start taking warfarin without having a group of people who don't require ACT. (Of course, thinking back to my days in research, it may be argued that the fact that you have a heart defect, DVT or AFIB makes you DIFFERENT from those who don't and it's THE FACTOR that made you different or predisposed you to certain cardiac problems that make your response to warfarin different from the response of a person without those issues).
As far as tihis study is concerned, I didn't see tht it requires people who aren't already taking warfarin to participate. Even a simple survey of some of the thousands who take warfarin to learn their weekly dosing, activity levels, etc. and to determine the presence or absence of the genes they're searching for, should provide pretty good indication of biological response to Warfarin. This woudl a a 'retrospective' study - and may be somewhat easier to run than the 'prospective' one they appear to be proposing.
Although the study may help to get to the 'truth' about the responses of people with these genes to Warfarin - and may help with recommendations for starting doses, I'm not entirely convinced that it won't replace careful INR monitoring when warfarin is started, and regular monitoring until the INR stabilizes. Plus - there's been speculation that other drugs may replace warfarin before this decade is out. Although the new medication willl probaby cost much more than generic warfarin, it may become more of a standard (if it's safer) than warfarin, making this research interesting - but of little value.
