Genetic link found to colon cancer in study

By Andrew Stern

CHICAGO (Reuters) - A gene related to a hormone secreted by the body's fat cells may lower the risk of colon cancer, a discovery that could reassure people with a family history of the disease, researchers said on Tuesday.

The gene variation, shared by about half of all those in the study, likely helps control how much of the hormone adiponectin fat cells secrete, the researchers reported in the Journal of the American Medical Association.

People with more of the hormone in their blood are known to have a lower risk of colon cancer, but the body's mechanism for controlling adiponectin secretion by cells is unclear.

The hormone suppresses inflammation of blood vessels, can raise the body's metabolic rate, and is known to lower the risk of colon and breast cancer.

Obese people, who have a higher risk of cancer, tend to have less of the hormone. People with more adiponectin have less risk of heart disease and diabetes.

The researchers reported on two groups totaling 1,500 people.

New Yorkers of Ashkenazi Jewish ancestry who had the gene were 28 percent less likely to have been diagnosed with colon cancer. The disease is more common in Ashkenazi Jews -- who originated in Europe -- than the general population.

The other group, from Chicago, was diverse ethnically and those with the gene had a 52 percent lower risk.