Mom's Environment During Pregnancy can Affect her Grandchildren

Starving a pregnant mouse can cause changes in the sperm of her sons that apparently warp the health of her grandchildren, according to a new study. The finding offers some of the strongest evidence yet that a mother’s environment during pregnancy can alter the expression of DNA in ways that are passed on to future generations.

A number of studies have suggested that environmental stresses in a parent may harm the health of subsequent generations. For example, women who were pregnant during a 1944 famine in the Netherlands known as the Dutch Hunger Winter had children and grandchildren who were unusually small or prone to diabetes and obesity. Animal studies have also found that a stress to a parent, such as exposing a pregnant mouse to toxic chemicals or mildly shocking a mouse father to make it fear an odor, can result in effects such as infertility or changes in behavior that persist for two generations or more yet can’t be explained by genetic mutations.

Some scientists suspect that the effects are passed down via so-called...