南亚基因组研究揭示饮奶习惯的起源

Natural selection was at work—but only in populations with no alternative to dairy MICHAEL PRICE S outh Asia, where dairy products such as yogurt, paneer, and ghee are dietary staples, is helping solve a long-standing puzzle about how humans gained the ability to digest milk. Babies around the world produce an enzyme called lactase that breaks down the sugars, or lactose, in breast milk, but most people lose this ability as they age and suffer digestive problems when they drink milk. However, certain people can make that enzyme into adulthood—a trait known as lactase persistence—allowing them to consume milk and other dairy products. …