Gene May Affect Neural Tube Defects

April 4, 2007 -- Scientists have spotted three gene mutations that may make neural tube defects such as spina bifida more likely.

All three mutations are in the VANGL1 gene, the researchers report in The New England Journal of Medicine.

The VANGLI gene is a potential risk factor in human neural tube defects, note the researchers.

They included Zoha Kibar, PhD, of the biochemistry department at Montreal's McGill University.

However, the researchers aren't blaming all neural tube defects on VANGL1 gene mutations.

The exact cause of neural tube defects isn't known. A complex mix of genetic and environmental factors is likely involved, Kibar's team notes.

About Neural Tube Defects

"Neural tube defects are major birth defects of a baby's brain or spine. They happen when the neural tube (which later turns into the brain and spine), doesn't form right, and the baby's brain or spine is damaged. This often happens within the first few weeks of pregnancy, often before a woman knows she is pregnant," states the CDC.

Getting enough folic acid (folate) reduces the risk of having a baby with neural tube defects.

The CDC recommends that every woman of childbearing age take 400 micrograms (mcg) of folic acid daily in a vitamin or in foods that have been enriched with folate.

That recommendation includes women who aren't planning to get pregnant, since many pregnancies are unplanned. Folic acid supplementation should start before pregnancy, notes the CDC.

Gene Study

Neural tube defects affect one to two infants per 1,000 births, Kibar's team notes.

Based on studies in animals, the researchers studied the VANGL1 in 144 people with neural tube defects and 106 people without neural tube defects.

Participants lived in Italy or France. Most were studied at a hospital in Genoa, Italy; seven were studied in Paris.

Three Italian patients with neural tube defects had mutations in their VANGL1 gene. Each of those patients had a different VANGL1 gene mutation.

Kibar and colleagues haven't proved that VANGL1 gene mutations cause neural tube defects. As the study shows, most patients with neural tube defects didn't have VANGL1 gene mutations.

However, the findings "implicate VANGL1 as a risk factor in human neural-tube defects," write the researchers.

They call for further studies on the VANGL1 gene and neural tube defects. For instance, Kibar's team suggests studying how VANGL1 gene mutations respond to folic acid supplementation.