Scientists have found that a gene carried by up to 85 percent of the people in the world increases the risk of developing diabetes by about 25 percent.
The increase, compared with that of people having a subtly different form of the gene, is relatively modest but significant, say investigators who report their study in the September Nature Genetics. "Although [the gene] has a very weak effect on the individual, because it is so common, it has a pretty big effect on the general population," notes coauthor David Altshuler of the Whitehead Institute for Biological Studies in Cambridge, Mass.
The gene, which encodes a protein called peroxisome proliferator-activated receptor-gamma (PPAR-gamma), seems to influence a person's chance of developing the most common form of diabetes. Known as noninsulin-dependent, or type II, diabetes, this disorder generally occurs when the body has trouble responding to the hormone insulin, which controls blood sugar.