Pah gene refers to the phenylalanine hydroxylase gene, which is responsible for encoding a specific enzyme called phenylalanine hydroxylase (PAH). This gene is located on chromosome 12q22-q24.2 in humans.
Phenylalanine hydroxylase is a vital enzyme involved in the metabolism of the amino acid phenylalanine. It catalyzes the conversion of phenylalanine into another amino acid called tyrosine. Tyrosine is subsequently utilized in the synthesis of various important molecules like neurotransmitters (e.g., dopamine, epinephrine, and norepinephrine), thyroid hormones, and melanin.
Mutations or alterations in the pah gene can lead to phenylketonuria (PKU), an inherited metabolic disorder. Individuals with PKU have a deficiency or complete absence of functional phenylalanine hydroxylase. As a result, phenylalanine cannot be properly broken down, leading to its accumulation in the body.
The buildup of phenylalanine can have detrimental effects on the central nervous system, causing cognitive and neurological impairments if not managed properly. Newborns are typically screened for PKU shortly after birth, as early diagnosis allows for the prompt implementation of dietary modifications, including a low-phenylalanine diet.
In summary, the pah gene encodes the phenylalanine hydroxylase enzyme, which is essential for the breakdown of phenylalanine. Mutations in this gene can cause PKU, a disorder characterized by the accumulation of phenylalanine and subsequent neurological complications.
