Researchers have found a genetic link between obesity and colon cancer that may help pave the way for more effective screening tests for the disease. It may also lead to greater accuracy in predicting the people who are at the greatest risk of the disease, experts say.

People who inherit a variation of a gene called ADIPOQ, which results in the formation of a fat hormone called adiponectin, are 30 percent less likely to develop colon cancer, say researchers from University of Alabama Comprehensive Cancer Center.

Those without this gene variant, or who have excessive blood levels of the fat hormone, are at a greater risk and should get regular screenings for the disease.

Previous research has found that colon cancer risk rises with increasing weight, but this finding point to a genetic reason for the link. It is not yet clear if people without this gene variant can reduce their risk of colon cancer through diet and exercise, the researchers noted.

Colon cancer is the third deadliest cancer in the United States with nearly 150,000 Americans diagnosed each year, according to estimates from the American Cancer Society. The report was published in the Oct. 1 issue of the Journal of the American Medical Association.