Evolution & origins of complexity

Scientists discover inherited traits that break Mendel's Laws of genetics

We all learned Mendel: traits come from your DNA sequence, inherited in tidy ratios. New work says biology bends that rule more often than we thought.

Scientists discover inherited traits that break Mendel's Laws of genetics
Visual brief for “Scientists discover inherited traits that break Mendel's Laws of genetics”.

What happened

Researchers at Johns Hopkins Medicine and Texas A&M, led by Andrew Feinberg, found that about 7% of epigenetic inheritance patterns are non-Mendelian. They also documented the first known paramutation in a mammal, at the Capn11 gene, where one version of a gene can durably alter how its partner behaves and pass that change to the next generation.

This matters because it widens what counts as heritable. Some traits and disease risks may travel through chemical marks layered on top of DNA, not just the letters themselves. That has real implications for how we think about evolution, health, and what we inherit.

Textbook rules are starting points, not walls. The genome is more dynamic, and more interesting, than the clean ratios suggested. Always a good day when a 150-year-old rule gets an asterisk.

Source

Reported by Scientists discover inherited traits that break Mendel's Laws of genetics via sciencedaily.com, published June 1, 2026.