When they created mice missing a mysterious new gene, researchers expected them to die of cancer. It never happened -- but what did happen may one day lead to new treatments and tests for diabetes.

"At first, we planned to develop the mice because we thought their missing gene was needed to prevent normal cells from becoming cancer cells, and so they would start to grow tumors," Stéphane Schurmans, MD, PhD, tells WebMD. "But when we had the mice in hand, we never saw that happen. Instead, we saw that they died in a few days from very low blood sugar. So we thought 'Ah! Maybe this is not an [antitumor] gene. Maybe it is a hormone-signaling gene.' In fact, after several months, we found that it controls [a cell's response to] insulin."

Insulin is the hormone that helps the cells of our body get sugar from the bloodstream, which can be used for energy. People with type 2 diabetes become resistant to insulin, meaning that their cells don't take up the sugar like they should in response to insulin. Current treatments for this type of diabetes either causes the body to make more insulin, gives the body insulin directly via injection, or increases the body's ability to sense when insulin is present. Schurmans' team's findings point to a new target: Reduce insulin resistance by increasing the response of the cells to insulin itself.

"This is [an] opportunity to develop drugs that will decrease the resistance to insulin in people with diabetes," Schurmans tells WebMD.

Schurmans and co-workers at the Interdisciplinary Research Institute in Brussels, Belgium, were the first to discover the gene that, when activated, produces the substance known as SHIP2. Discovered only in 1997, SHIP2 belongs to a little-understood family of human enzymes that put the brakes on important cell functions and helps keep them from running wild. In this case, SHIP2 reduces a cell's response to insulin. Schurmans says that his team has cloned a human SHIP2 molecule that has the same function as mouse SHIP2.

The finding that the SHIP2 gene may be linked to diabetes suggests that people carrying a mutant version of the gene may be particularly susceptible to getting type 2 diabetes.

"If we find a mutation in that gene in diabetes patients but not in healthy people, it would be one of the first genes known to predispose a person to get type 2 diabetes," Schurmans says. "Perhaps soon it will be possible to know when to tell relatives of a diabetes patient, 'You are at risk and should see your physician more often."

While the Belgian researchers are enthusiastic about their discovery -- and its publication in the prominent scientific journal Nature -- they warn that their research is still in its early stages. University of Chicago geneticist Nancy J. Cox, PhD, sounds a similar warning.

"It's an extremely interesting gene, and [what happens in their mice] is very interesting," Cox tells WebMD. "I don't know if the human gene will have anything to do with human diabetes -- but it's an outstanding candidate [for a] diabetes gene and will be interesting to follow up in human studies."

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