Concept explainers
The human AMY-1 gene encodes salivary amylase, an enzyme that breaks down starch. The number of copies of this gene varies, and people who have more copies generally make more of the enzyme. In addition, the average number of AMY-1 copies differs among cultural groups.
George Perry and his colleagues hypothesized that duplications of the AMY-1 gene would confer a selective advantage in cultures in which starch is a large part of the diet. To test this hypothesis, the scientists compared the number of copies of the AMY-1 gene among members of seven cultural groups that differed in their traditional diets. The Figure shows their results.
Starchy tubers are a mainstay of Hadza hunter-gatherers in Africa, whereas fishing sustains Siberia’s Yakut. Almost 60% of Yakut had fewer than 5 copies of the AMY-1 gene. What percentage of the Hadza had fewer than 5 copies?
FIGURENumber of copies of the AMY-1 gene among members of cultures with traditional high-starch or low-starch diets.
Source: G. Perry et al. 2007. Diet and the evolution of human amylase gene copy number variation. Nature Genetics 39:1256–1260.
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Chapter 47 Solutions
Biology: The Dynamic Science (MindTap Course List)
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- What are some metabolic adaptations (for example, lactose tolerance in groups derived from herders) found in modern-day humans and Neanderthal genetics?arrow_forwardUsing a research to defend your position,can we draw a straight line and suggest only one specific choice of diet or should we look into combined diet solutions?arrow_forwardExplain why wastage of essential amino acids can occur and how eating two foods simultaneously can prevent wastage.arrow_forward
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