Dr Peadar Kirke, a public health expert at the Health Research Board in
Dublin, and colleagues in Ireland and the United States identified an altered
gene that raises the odds of neural tube defects such as spina bifida after
studying nearly 400 people born with a defect and more than 800 healthy
volunteers.
The genetic variation puts half the population at an increased risk of neural
tube defects, according to the researchers.
"Our study provides new data underscoring the importance of public
health...programs of folic acid supplementation and food fortification targeted
at all women of childbearing age to prevent neural tube defects," Kirke said in
a report published online by the British Medical Journal on Friday.
About 40 percent of the population have one copy of the altered gene and 10
percent have two copies.
"The genetic variant is very common," Kirke said in an interview.
He advised women to take supplements of folic acid before getting pregnant
and afterwards to prevent neural tube defects.
Folic acid is a synthetic compound of folate, a B vitamin found in green
leafy vegetables and liver. Women are advised to take supplements before
conceiving and during the early months of pregnancy.
Neural tube disorders occur during the early development of the fetus when
the spine does not close properly. Spina bifida, a defect of the spinal column,
is the most common of them.
The United States started fortifying flour with folic acid several years ago
after its role was established in reducing birth defects. Since then the number
of babies in the United States born with spina bifida or another serious defect
called anencephaly has fallen by about 26 percent.
Kirke said his findings provide further evidence for food fortification with
folic acid.
Scientists have also found that daily supplements of folic acid or food
fortified with it can help to prevent heart disease, stroke and blood clots.
Folic acid breaks down a substance in blood called homocysteine which is a
cause of heart attack and stroke.
