DNA knowledge of limited use
Does knowing your genetic make-up increase your chances of avoiding disease?
As scientists try to reduce the cost of doing a high-quality analysis of a person's total DNA structure from US$10 million in 2004 to US$1,000 or less, Harvard School of Public Health researchers have found that detailed knowledge about your genetic make-up may change your estimated disease prediction risk for three common diseases by only a few percentage points. That's typically not enough to make a difference in prevention or treatment plans, they say.
Knowing one's genetic make-up means understanding the interplay with other genetic variants, or with environmental risk factors. Scientists have long hoped this information could improve disease risk prediction enough to help in prevention and treatment.
But the Harvard study, published online last week in The American Journal of Human Genetics, found that 'the benefit of such a discovery for risk prediction purposes might be very limited', according to lead author Hugues Aschard, research fellow in the epidemiology department.
The team examined whether disease risk prediction would improve for breast cancer, type 2 diabetes and rheumatoid arthritis if they included the effect of synergy in their statistical models.
But for each of these disease models, researchers calculated that the increase in risk prediction sensitivity - when considering the potential interplay between various genetic and environmental factors - would only be between 1 per cent and 3 per cent at best.
