Question

Phenylketonuria is due to deficiency of:

• A. Phenylalanine
• B. Phenylalanine hydroxylase
• C. Phenylene
• D. All of these

Answer 1

The Correct Option is B

Phenylketonuria (PKU) is a genetic disorder characterized by an inability to properly metabolize the amino acid phenylalanine. This condition is specifically due to a deficiency of the enzyme phenylalanine hydroxylase. Under normal conditions, phenylalanine hydroxylase converts phenylalanine into tyrosine, another amino acid that is important for protein synthesis and production of neurotransmitters.

In individuals with PKU, this metabolic pathway is disrupted due to the insufficient activity of phenylalanine hydroxylase. As a result, phenylalanine accumulates in the body to toxic levels, which can lead to intellectual disabilities and other complications if not managed with a controlled diet.

Therefore, the correct answer is Phenylalanine hydroxylase.