A study in mice finds that for certain genes, one parent’s allele can dominate expression and shape behavior—and which parent’s allele does so varies throughout the body.
In mice, epigenetic marks made on histones during infancy influence depression-like behavior during adulthood. A drug that reverses the genomic tags appears to undo the damage.
Evidence is mounting that epigenetic marks on DNA can influence future generations in a variety of ways. But how such phenomena might affect large-scale evolutionary processes is hotly debated.