Probing genes for disease risk

New research by Alkes Price, associate professor of Statistical Genetics at Harvard School of Public Health, and colleagues focuses on new approaches to characterizing and identifying genetic factors in complex disease.

HSPH: What’s the basic finding of your new research?

PRICE: Our study could help scientists determine the best way to search for genetic risk factors associated with disease. The study outlines a new way of estimating how much of variation in a particular trait is due to genetics. Examples we looked at in our paper include height, body mass index, and prostate cancer. Until about five years ago, the amount of variation in diseases or traits that is determined by genetic variation — called heritability — had been based on studies of twins, which look at differences in disease or trait values among identical vs. fraternal twins. In our new study, we describe an approach that relies instead on populations of mixed ancestry called “admixed” populations — in this case, African Americans, who inherit ancestry from both African and European ancestors. It’s useful to study these populations because — even though genetic differences between populations are generally much smaller than genetic differences within populations — the genomes of different continental populations contain valuable clues that can help geneticists determine the best way to search for genetic disease risk factors.