Life-Style Genetic Tests Have Limited Clinical Use

Genetic tests indicating risk of diseases based on genetic markers have gained in popularity and consumer acceptance over the last decade although regulators have frequently questioned the accuracy and clinical benefit of such tests. Genetic tests on otherwise healthy individuals to look for genetic markers and predicting the likelihood of getting a given disease are called “Life-style” tests since they are not considered diagnostic in nature but informative. Companies selling genetic tests tout their value in creating awareness at the individual level in terms of likelihood of getting a given disease in future, and hence encouraging changes in behavior to delay or reduce the chances  of that disease in that individual. For example, knowing that one is prone to cardiac disease could prompt the individual to live a healthier life style to reduce or delay the occurrence of cardiac disease. However, two surveys, one done in 2010 and another published this month debunk the basic tenet justifying genetic tests. In a study published in British Medical Journal this week, it was found that knowing the genetic likelihood of getting a given disease or habit such as smoking, had no effect on the behavior of the relevant individuals. There were no changes in smoking, diet, alcohol consumption, frequency of exercise, or attendance at screening or behavioral support programs linked to an individual finding out his or her genetic probability of having a behavior or life-style related disease. The results may seem surprising to some but seem indicative of what would be expected of human behavior. We do things knowing the risk and probability of injury. Knowing genetic risk should be no different. It works the other way around as well. The curiosity to know more about one’s genetic markers and probability of disease is strong so the popularity of such “life-style” genetic tests should not be affected by this report. The regulatory acceptance of such tests, on the other hand, will be certainly be impacted as it gives the regulators of both market approval and marketing practices, food of debate if such tests can make the desired claims about utility of such tests. FDA has been very aggressive in terms of restricting the claims and availability of life-style genetic tests, and this report will only make it so much more hard for the developers and marketers of such tests.