(Ivanhoe Newswire) -- New research confirms a previous finding -- a variant in a gene called "transcription factor 7-like 2" (TCF7L2) increases the risk of type 2 diabetes.

The results come from the Diabetes Prevention Program (DPP), a large study of 3,548 adults at risk for developing type 2 diabetes. Researchers found one copy of the risk variant in 40 percent of DPP participants and two copies in 10 percent. Researchers say for those who inherited two copies, the risk of developing diabetes is about 80-percent higher than it is for non-carriers.

The characteristics of type 2 diabetes are insulin resistance and a gradual failure of beta cells to produce enough insulin. The study reveals this variant of TCF7L2 is linked with decreased insulin production but not with any increase in insulin resistance.

"Our data, combined with previous longitudinal studies and genetic findings, show that type 2 diabetes can be triggered by decreased insulin production and not just by insulin resistance," reports lead author Jose Florez, M.D., Ph.D., of Massachusetts General Hospital in Boston. "However, researchers need to learn more about this gene before they can even begin to translate the discovery into a drug treatment that benefits people with diabetes or those at risk."

Even though this gene variant can predict a greater risk of developing type 2 diabetes, the researchers do not recommend routine genetic testing for it. They say there is not enough evidence a test would mean better outcomes or that it would be cost-effective.
 

SOURCE: The New England Journal of Medicine, 2006;355:241-50