A recent pub led by a talented research team might call for a ceasefire in the old “nature vs. nurture” argument. Researchers in The Netherlands and the U.S. say their new study on people conceived or born during the Dutch Famine of 1944-1945 piles on even more evidence that the prenatal environment and your genes can affect DNA methylation independently and additively.
Even though previous studies strongly suggested that the prenatal environment and genetics separately affect DNA methylation, the combined effects on one locus were still unknown. To find out, the researchers zeroed in on nine regulatory loci in five differentially methylated regions (DMRs) within the well-defined IGF2/H19 locus. DNA methylation at one of the DMRs at that locus has been associated with both prenatal exposure to the Dutch Famine and genetics, so they figured that would be a good place to look. Here’s what they found:
- Widespread but small differences in DNA methylation were evident in the famine-exposed people compared to the controls.
- Similar results were found for SNPs—widespread but small differences.
- Genetic variations (SNPs) and famine exposure were both independently linked to DNA methylation at the same DMRs. The effects were also additive.
The team reasons that such widespread small changes could be a way to fine-tune how pathways work in the body.
The results suggest that “for some loci, epigenetics may be the information layer in which the classical contrast between ‘nurture’ and ‘nature’ debate comes to a modern molecular synthesis,” they say.
Digest the details at PLoS One, May 2012.