Large dogs age faster than small dogs due to epigenetic mechanism, study finds

In October’s research roundup, a study published in Science explains why larger dogs tend to age faster than smaller ones. Arizona State University scientists found that the difference in lifespan is linked to “jumping genes,” or transposable elements, that influence DNA methylation patterns.

Using data from 864 dogs in the Dog Aging Project, the researchers mapped genome‑wide DNA methylation—a chemical marker that regulates gene activity and changes over time. The study shows that these epigenetic changes, rather than fixed genetic sequences, correlate with the accelerated aging seen in larger breeds.

Because dogs exhibit a clear inverse size‑lifespan relationship, they serve as a valuable model for biologists studying aging mechanisms across mammals.