In humans the AMY1 gene produces the enzyme amylase in cells

In humans, the AMY1 gene produces the enzyme amylase in cells of the salivary glands. Amylase breaks down starch (a polysaccharide) into the sugar maltose (a disaccharide). People from cultures with diets high in starch produce more amylase than people from cultures with diets low in starch because of a mutation in the AMY1 gene. Explain in two to three sentences why the frequency of this AMY1 mutation would have increased in frequency in populations with a high- starch diet.

Solution

People from cultures with diets high in starch produce more amylase as there occurs selection for increased amylase production.Since these people eat high-starch diets, high amounts of amylase is required so that the starch can break down in the mouth easily thus aiding in efficient digestion.People from cultures with diets low in starch have a mutation in the AMY1 gene as there is no advantage in producing more amylase if their diet is low in starch as there will be not that much requirement for the amylase enzyme.