Question

A diet that restricts phenylalanine and supplies tyrosine is the only current treatment for people born with the single-gene disorder _________.

A. DNA
B. ALS
C. PKU

Answer 1

Option (C), A diet that restricts phenylalanine and supplies tyrosine is the treatment for the single-gene disorder known as phenylketonuria (PKU). People with PKU lack the enzyme needed to convert phenylalanine to tyrosine, leading to toxic levels that can cause severe brain damage if not managed.

Step-by-step explanation:

The single-gene disorder that requires a diet restricting phenylalanine and supplying tyrosine is known as phenylketonuria (PKU). In individuals with PKU, there is insufficient activity of the enzyme phenylalanine hydroxylase, which is necessary to convert phenylalanine to tyrosine.

Due to this deficiency, phenylalanine accumulates to toxic levels in the body, risking brain damage and severe mental ret_ardation. Hence, a very low protein diet and avoidance of the alternative sweetener aspartame, which contains phenylalanine, as well as foods high in this amino acid, is critical to manage the disorder.