Question

As we age, the amount of phenylalanine used in the body to synthesize proteins gradually decreases. After birth, about 0.5 grams of phenylalanine are consumed daily, which increases to 4 grams in children and adults, most of which is oxidized into tyrosine. This process mainly relies on phenylalanine hydroxylase and also requires the participation of cofactors. If this oxidation process is impaired, phenylalanine will accumulate in the body.

Answer

Phenylalanine metabolic disorders are primarily caused by a deficiency in an enzyme called phenylalanine 4-monooxygenase. This enzyme is responsible for oxidizing phenylalanine into tyrosine. If this enzyme is deficient or its activity is reduced, phenylalanine will accumulate in the body, leading to a series of health problems, including developmental delays in intelligence and skin disorders. Additionally, phenylalanine metabolic disorders may also be related to genetic factors; if someone in the family has this disease, others may also have an increased risk of developing it.