An extra dose of vitamin B3 might help prevent certain kinds of complex birth defects, according to a new study. It is thought the vitamin can help compensate for defects in the body’s ability to make a molecule, nicotinamide adenine dinucleotide (NAD), which researchers have now linked for the first time to healthy fetal development in humans.
Every year 7.9 million babies are born with a birth defect worldwide. The discovery suggests the possibility that boosting levels of B3 in pregnant women’s diets might help lower overall rates of birth defects.
Researchers from the Victor Chang Institute in Sydney called it ‘a double breakthrough’ as they found both a cause and a preventative solution. The researchers analysed the DNA of four families where the mothers had suffered multiple miscarriages or their babies were born with multiple birth defects, such as heart, kidney, vertebrae and cleft palate problems.
They found mutations in two genes that caused the child to be deficient in a vital molecule known as Nicotinamide adenine dinucleotide (NAD), which allows cells to generate energy and organs to develop normally. Lead researcher Prof Sally Dunwoodie replicated these mutations in mice and found they could be corrected if the pregnant mother took niacin (vitamin B3).
“You can boost your levels of NAD and completely prevent the miscarriages and birth defects. It bypasses the genetic problem,” she said. “It’s rare that you find a cause and a prevention in the same study. And the prevention is so simple, it’s a vitamin,” she said.
Back In 2005, Dunwoodie’s team dealt with a particularly severe case, a baby who had major defects in the heart, backbone, and ribs; the rib problems being so bad that the child’s lungs couldn’t fully inflate. The team found that the family carried a mutation in a gene related to the production of NAD, a molecule crucial for energy storage and DNA synthesis in cells. Both parents carried a mutation in one of their copies of the gene, and the affected baby had inherited two defective copies.
No one had reported any role for NAD in heart or bone development, Dunwoodie says. “We didn’t know what to do with it.”
To confirm the role of the mutations in organ and bone development, the researchers knocked out the two genes in mice to see whether similar birth defects appeared. At first all the pups were normal. But then the researchers realised that standard mouse chow is rich in niacin and that cells can use either niacin or nicotinamide—both known together as vitamin B3—to make NAD by an alternate pathway.
The work opens a potentially exciting new area of research for developmental biologists: Trying to understand how cell metabolism affects development
