This is the VOA Special English Health Report.

A new study has found that a fat cell gene may reduce the risk of colon cancer in some people. The study provides what scientists say is the first evidence of a genetic link between a fat cell gene and colon cancer. The research could lead to better tests for the disease as well as measures to help prevent it.

A doctor in Plano, Texas, performs a colonoscopy on a patient

Current evidence suggests a relationship between obesity, insulin resistance and colon cancer risk. The scientists say what they have found now is an area of a gene that is connected with the cancer risk. They say this area is most likely not the cause of the disease, but they think it is where the connection comes from.

The gene is involved in the formation of a hormone called adiponectin. Some people have higher levels of this hormone in their blood, others have lower levels. Higher levels have been linked with lower rates of obesity and insulin resistance. And lower levels have been linked with higher rates.

The Journal of the American Medical Association published the new findings last week. Boris Pasche from the Comprehensive Cancer Center at the University of Alabama at Birmingham led the research.

Colon cancer is one of the leading causes of cancer deaths. Every year it kills almost six hundred eighty thousand people around the world. And doctors find more than one million new cases. The disease is highly treatable if discovered early.

The research involved two studies with a total of about one thousand five hundred people. The larger of the two studies involved New Yorkers of Ashkenazi Jewish ancestry. Colon cancer is more common in Jews of eastern European ancestry than in the general population. The other study involved people of different ethnicities from Chicago, Illinois.

Currently, in the United States, the general advice is for colonoscopy tests for colon cancer to begin at the age of fifty. A colonoscopy can find and remove growths before they become cancerous. But the test is invasive and can be uncomfortable.

A study last month in the New England Journal of Medicine expressed support for a test called a virtual colonoscopy. It uses X-ray and computer technology to search for growths, but cannot remove them. There are still some questions about the effectiveness of a virtual colonoscopy compared to a traditional one. But doctors hope it might appeal to people who would otherwise not be tested at all.

And that's the VOA Special English Health Report, written by Caty Weaver. I'm Steve Ember.