Those with the mutation produce lactase throughout their lives.
有这个突变基因人一生都可以生成出乳糖。
Different enzymes help to break different linkages - for example amylases break down large polysaccharides like starch into smaller units, whereas lactase, sucrase, and maltase break down lactose, sucrose, and maltose into their monosaccharides.
不同消化能分解特定糖链,比如淀粉可以将淀粉等多糖分解为小分子糖,而乳糖、蔗糖、麦芽糖则分别可将乳糖、蔗糖、麦芽糖降解为相应单糖。
Today nearly 90 percent of adult Britons and Scandinavians can chug all the milk they want, whereas down toward the Mediterranean, probably less than 40 percent have lactase persistence, and fewer than ten percent in Africa and Asia.
今天,近 90% 英国和斯堪纳维亚成年人可以喝他们想喝所有牛奶,而在地中海地区,可能只有不到 40% 人有乳糖耐受性,在非洲和亚洲只有不到 10%。