One Explanation for the Increased Incidence of Allergies Is the Hygiene

question 10

Essay

One explanation for the increased incidence of allergies is the hygiene hypothesis. It suggests that a lack of early childhood exposure to infectious agents and later a lack of exposure to helminths as adults increase susceptibility to allergic diseases. How would you explain why people living in modern hygienic conditions have more allergies? Do you believe they are exposed to more allergens or that having less infectious agents makes one more likely to react to allergens? Explain your decision and describe what experiments or observations would be necessary to support your explanation.

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Definitions:

Gene Recruitment

The evolutionary process by which a gene acquires a new function.

Complex Adaptation

A complex adaptation is a suite of coexpressed traits that together experience selection for a common function. Phenotypes are considered complex when they are influenced by many environmental and genetic factors and when multiple components must be expressed together for the trait to function.

Citrate Exploit

The ability of certain bacteria, specifically strains of E. coli in experimental evolution, to utilize citrate as a carbon source under aerobic conditions where they typically cannot.

Lenski's Experiment

A long-term evolution experiment led by Richard Lenski, observing the genetic changes in Escherichia coli bacteria over thousands of generations.