SCIENCE / MEDICINE : Blood Test Locates Gene Tied to Juvenile Diabetes

A new blood test that identifies a gene associated with juvenile diabetes should allow doctors to more accurately predict which children may get the disease, scientists reported last week in the New England Journal of Medicine.

Researchers at the University of Texas Southwestern Medical Center in Dallas said the test is five times more accurate than existing genetic screens for juvenile diabetes, which affects about one in 200 people in the United States. But the team cautioned that the test can determine only whether a child has a higher than usual chance of developing the disease--not whether he or she definitely will get it.

Using the test, researchers found that a gene that appears to offer protection against juvenile diabetes was detected in only six of 266 patients with the disease, but was present in 74 of 203 people tested who were free of diabetes. In contrast, a gene associated with greater susceptibility to juvenile diabetes was found in 154 of the diabetes patients but only 38 of those without the disease.

Juvenile diabetes, also known as insulin-dependent diabetes, occurs when cell destruction leaves the pancreas unable to produce insulin--frequently leading to such complications as weight loss, kidney failure and blindness.