Final answer:
Phenylketonuria (PKU) is a genetic disorder caused by a mutation in the gene that codes for the enzyme phenylalanine hydroxylase. It is an example of gene-environment (G-E) interaction, as the severity of the condition can be influenced by environmental factors, specifically diet. By following a strict diet low in phenylalanine, individuals with PKU can mitigate symptoms and prevent neurological damage.
Step-by-step explanation:
Phenylketonuria (PKU) is an example of gene-environment (G-E) interaction. PKU is a genetic disorder caused by a mutation in the gene that codes for the enzyme phenylalanine hydroxylase. This enzyme is responsible for breaking down phenylalanine, an amino acid found in protein-rich foods. People with PKU lack the ability to properly metabolize phenylalanine, leading to its accumulation in the body.
Although PKU is a genetic disorder, the severity of the condition can be influenced by environmental factors. The symptoms and complications of PKU can be mitigated by following a strict diet that is low in phenylalanine. By controlling the intake of phenylalanine through diet, individuals with PKU can prevent the toxic build-up of phenylalanine and avoid the associated neurological damage.
Therefore, phenylketonuria represents a clear example of how the interaction between genetic factors (mutation in the phenylalanine hydroxylase gene) and environmental factors (diet low in phenylalanine) can determine the expression and severity of a genetic disorder.