Phenylketonuria (PKU) is caused by the absence of the enzyme phenylalanine hydroxylase, which catalyzes the first step of the pathway that breaks down the amino acid phenylalanine, a common component of dietary protein
Explain how environmental intervention is commonly practiced to prevent the development of this human autosomal recessive condition.
PKU damages neurons because the body is unable to break down dietary phenylalanine, ultimately causing irreversible mental retardation and neuron death. There are two main ways in which the environment has been changed to affect the development of PKU. First, newborns are routinely screened for PKU so they can be placed on a phenylalanine-free diet and will avoid PKU complications. Second, individuals living with PKU are warned of foods containing phenylalanine by strict labeling of foods (e.g., foods and beverages containing the artificial sweetener aspartame). Thus, while they will always have the mutated allele, they are able to avoid developing the disease through strict control of diet.
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