Most of us have a hard time keeping up with the latest health recommendations . . . what’s good one year turns out to be a bad idea the next (kinda like the final season of Lost). For years, doctors have been telling women to take folic acid supplements before and during pregnancy to prevent neural tube defects in their babies. But when reports surfaced that linked maternal folic acid intake to an increased risk of asthma in children, some people began to question that recommendation. A new study may relieve some of those fears by showing that folic acid use before and during pregnancy has favorable effects on the methylation of the insulin-like growth factor 2 (IGF2) gene in infants, possibly reducing their risk of several chronic diseases.
Folic acid is an important donor of methyl groups for the DNA methylation of CpG dinucleotides. Scientists have linked aberrant methylation of the imprinted IGF2 gene to an increased risk of cancer and other chronic diseases. So researchers at Duke University and M.D. Anderson Cancer Center examined the methylation states of two differentially methylated regions (DMRs) that regulate IGF2 expression in the newborns of 438 women with no, moderate, or high folic acid use before and during pregnancy. Hypomethylation of the IGF2 DMR and hypermethylation of the H19 DMR have been associated with increased IGF2 transcription and cancer. Sodium bisulfite pyrosequencing of umbilical cord blood leukocytes revealed:
- Methylation levels at the IGF2 DMR were similar regardless of folic acid intake
- Methylation levels at the H19 DMR decreased with increasing folic acid intake before and during pregnancy
- The methylation decrease at the H19 DMR was largest in male and Caucasian infants
These findings support the notion that folic acid supplementation before and during pregnancy causes methylation changes that may benefit an infant’s long-term health, the researchers say. So for now at least, it looks like folic acid supplements are still the way to go for moms-to-be.
Read up on prenatal supplements at Epigenetics, July 2011