A research report provides a possible explanation for a class of birth defects that appears to be on the rise. A protein normally involved in programmed cell death may, as a consequence of high blood sugar, mistakenly tell cells of the nascent neural tube to die. Even with good control of diabetes, the risk for neural tube and other birth defects is two to five times higher than normal if a mother has the disease. That risk could increase as diabetes and obesity, both of which can cause high blood sugar, make inroads into younger populations. “I think there is a very large population of women at risk for having a baby with a neural tube defect who are not being looked at aggressively because they have not been diagnosed as being diabetic,” said Mary Loeken, Harvard Medical School assistant professor of medicine, “and yet their blood glucose may be higher than normal.” Such women might be advised to lower their blood sugar levels. The report appeared in the March 15, 2002 issue of the journal Genes and Development.