Twelve-year-old Joseph Cardenas has spina bifida, the most common disabling birth defect in the United States. It happens when the spine of the baby fails to close during the first months of pregnancy. Joseph has had some 6 or 7 surgeries.
"His is pretty high-level spina bifida," said Joseph's mother, Diana Cardenas. "It affected pretty much from his belly button all the way down."
Now researchers at UT Houston Medical School have discovered a link between the disease and genes regulating glucose metabolism. Geneticist Dr. Hope Northrup is one of the co-authors of the study.
"We're thinking that subtle defects in glucose regulation allow you to have slightly increased levels over someone else in the population, thus giving you this predisposition to this medical problem," she said.
Dr. Northrup says in Texas, nearly two out of every 1,000 babies born have spina bifida. And Hispanics are twice as likely to have a child born with it than any other ethnic group. Dr. Northrup isn't sure why. But she thinks it's related to a connection between Hispanics and native Americans.
"I think it is probably some of the variation in genes that we've gotten through our native American ancestry that are leading us to this point," said Dr. Northrup.
Diabetes is very common among native Americans. Northrup says taking folic acid daily can reduce a woman's risk of having a baby with spina bifida by as much as 70 percent. But it's little consolation for Diana, who learned too late.
"I was young when I had Joseph," she said. "So I really didn't look at my health the way I probably should have."
Diet and socio-economic status also play a role. But Northrup emphasizes that Hispanic women who are genetically at risk still have some control. If they take folic acid supplements, they will drop their baby's risk of spina bifida by 70 percent.