April 15 (Bloomberg) -- DeCode Genetics Inc., an Icelandic biotechnology company, will sell the first genetic test for type 2 diabetes risk in the U.S.

The test, called DeCode T2, identifies a gene variation that doubles the risk of diabetes, said Chief Executive Officer Kari Stefansson. DeCode's first marketed product, the test will cost about $500, he said. No sales projections have been made.

Spurred by rising rates of obesity and insufficient exercise, Type 2 diabetes affects 21 million Americans and is among the fastest-growing chronic diseases in the U.S. DeCode's test might help more than 50 million people on the cusp of diabetes understand their risk and perhaps use diet and exercise to avoid the disease, Stefansson said.

``This is a risk factor for diabetes that we have discovered,'' he said in a telephone interview. ``It's our duty to allow people to have themselves tested for it.''

The average person's risk of developing diabetes is about 7 percent. A positive result on DeCode's test raises the risk to about 14 percent, said Harvard Medical School's C. Ronald Kahn, head of obesity and hormone action research at the Joslin Diabetes Center in Boston. People who heed the test can cut their risk of diabetes with just modest activity and 500 fewer calories in their daily diet, he said.

``The information is valuable,'' Kahn said in a telephone interview, ``but reducing your risk from 14 percent to 7 percent might not be enough motivation for the average American citizen.''

Adult Onset

Type 2 diabetes, often called adult-onset, occurs when the body loses the ability to properly use insulin, the hormone that regulates blood sugar. Chronic high blood sugar levels are linked to severe disease of the eye, kidney, and heart, and lead to thousands of annual amputations and deaths.

Patients who lose sensitivity to insulin, a condition called ``insulin resistance,'' may be on the verge of diabetes or have the disease itself without knowing it. About 54 million Americans have abnormal blood sugar levels that may lead to diabetes, according to the American Diabetes Association.

Doctors will take a drop of blood or inner-cheek scraping from patients and ship it to DeCode and its collaborating laboratories for testing, which takes less than three weeks. Such laboratory tests don't require clearance by U.S. drug and device regulators.

About 8 percent to 11 percent of the population has two copies of the variation, called TCF7L2.

SNiPs

The test is an example of the power of testing for tiny genetic variations that signal larger disruptions in the genome. The variations, called single-nucleotide polymorphisms or SNiPs, are single-letter substitutions that can be identified with San Diego-based Illumina's gene arrays.

DeCode has tested thousands of people with the arrays to find SNiPs associated with diseases. Future tests may help determine whether patients will respond to drugs, diet, or other interventions, said John Buse, a professor of medicine at the University of North Carolina Chapel Hill and the ADA's president-elect for medicine and science.

``My guess is that some 10 or 20 years from now using genetic tests to predict response to therapy could be common,'' Buse said in a telephone interview.

To contact the reporter on this story: John Lauerman in Boston at jlauerman@bloomberg.net.

Last Updated: April 15, 2007 15:06 EDT