Nov. 2 (HealthDay News) -- New information about a protein in the pancreas may help in efforts to determine how diabetes develops during pregnancy, say Stanford University Medical Center researchers.

About 5 percent of women develop so-called gestational diabetes, which is a leading cause of birth defects and can predispose children to developing diabetes later in life.

In research with mice, the Stanford team focused on a protein called menin, which is known to have a role in preventing cancer in the pancreas and other organs. Menin prevents pancreatic cancer by blocking the growth of pancreatic cells.

However, insulin-producing islet cells in the pancreas need to grow during pregnancy in order to produce enough insulin. Therefore, the pancreas produces less menin during pregnancy. After pregnancy, menin levels go back to normal, and the islet cells return to their original size, the researchers explained.

They created mice that produced too much menin and found that there was insufficient islet growth during pregnancy, resulting in gestational diabetes.

"This suggests that there is an internal code for controlling pancreatic islet growth, a code we intend to crack," senior author Dr. Seung Kim, associate professor of developmental biology, said in a prepared statement.

Kim's team also found that the amount of menin present in the pancreas is regulated by a hormone called prolactin, which is abundant in pregnant women.

The research is published in the Nov. 2 issue of the journal Science.

SOURCE: Stanford University Medical Center, news release, Nov. 1, 2007