DNA and the Roots of Hair Roots
Posted on by Dr. Francis Collins
It’s intriguing to find the roots of physical traits: skin color, height, and those weird tufts of hair on Uncle Mike’s ears. We’re all curious to know why we look the way we do. But new technologies are allowing us to discover the precise genetic roots of human traits that vary across the world. Variations in our DNA have helped us resist diseases and adapt to different climates and foods, enabling us to colonize just about every environment on the planet.
Recent studies have pinpointed variations responsible for lighter skin in Northern climates (such as SLC24A5 ) and the ability to tolerate milk sugar (lactose) in adulthood . But a new NIH-funded study of a gene variant that arose in China adds a fascinating wrinkle—the use of a mouse model to help understand a potential human advantage . (Regular readers will note that last week in this space I wrote about how mouse models could sometimes be misleading—this week the mouse is a champion!)