Lactose Intolerance Essay

Lactose intolerance is a condition which stems from the body’s decreased expression of the LAC gene, which is used to create the enzyme lactase, which begins to diminish with age, starting from as early as the toddler years. Lactase, which is produced in the lining of small intestine, is needed in order to digest the complex sugars presented in milk, namely lactose. As expression of the LAC gene decreases, the resulting enzyme levels of lactase also dwindle. Resulting in the difficulties when digesting these sugars in milk products. The subsequent symptoms of lactose malabsorption include diarrhea, gas, bloating, flatulence, and abdominal pain (McKusick). Lactose intolerance is currently more globally common than its mutated counterpart, lactose tolerance. Although people with lactose intolerance may have a hard time digesting lactose, especially in fresh milk, they often are

The first being that data collected from the same specimen could vary greatly depending on the precise section of small intestine used in the experiment. However, the ratios of sucrase to lactase from individual specimens remained the same, meaning that the ratio of enzyme activity remained constant even in different parts of the small intestine. The data from the samples displayed a trimodal distribution, producing three distinct data groups, each corresponding to the different genotypes. Those homozygous dominant for lactose tolerance had the highest lactase enzyme activity, heterozygotes had a median amount of activity, and those homozygous recessive, who also displayed lactose intolerance, had little to no lactase activity. The calculated allele frequency for phenotype closely matched the expected result of a population in a Hardy-Weinberg equilibrium (Ho). This pattern is similar to that of incomplete dominance, where heterozygotes produce a third phenotype, with the trait being for lactase