Thousands of years ago, humans made a dangerous journey across the icy Bering Strait into the Americas. Now, scientists have discovered these ancient travelers carried something unexpected – a piece of DNA from extinct Denisovans that may have helped them adapt to their new home. A new study published August 21, 2025, in Science shows that a gene called MUC19, originally from Denisovans, is unusually common in people with Indigenous American ancestry. This gene plays a key role in the immune system by producing mucins – proteins that form protective barriers in the respiratory and digestive tracts. “In terms of … Continue reading One in Three Mexicans Carry Ancient Denisovan MUC19 Gene That Crossed 20,000-Year ‘Genetic Telephone’ Path