A mother’s age can shape her offspring without changing their DNA

A mother's age can influence her offspring's physical traits and behavior without altering their DNA. This phenomenon, known as maternal age effects, is prevalent across various animal species, from invertebrates to humans, elephants, and other primates. Despite its commonality, the biological processes behind these effects are still unclear.

Kristin Gribble, an associate scientist, leads research on rotifers, tiny aquatic animals that reproduce rapidly, to understand these maternal age effects. Her findings suggest that these effects may be controlled by epigenetic processes, specifically histone modifications, rather than by DNA mutations or cellular damage associated with aging.

The study also indicates that these effects can be reversed within a single generation, challenging the notion that they are caused by the gradual buildup of aging-related changes. Genetic differences may further determine how offspring are affected by an older mother. While advanced maternal age is often linked to negative outcomes, genetic factors might mitigate these effects or even produce benefits in some cases.

The persistence of maternal age effects across species remains an evolutionary puzzle, as conditions that benefit offspring from older mothers do not seem to be selected against due to weaker selective pressure in later life stages. Understanding maternal effects could provide insights into human health and lead to precision medicine approaches, as an individual's biology may also depend on the environment and conditions experienced by previous generations.