Gene PAH

Also known as

phenylalanine hydroxylase, phenylalanine-4-hydroxylase, PKU

Overview

PAH (Phenylalanine Hydroxylase) encodes the enzyme that converts the essential amino acid phenylalanine to tyrosine. This is a critical step in amino acid metabolism, as phenylalanine is obtained exclusively from the diet. The enzyme requires tetrahydrobiopterin (BH4) as a cofactor and is expressed primarily in the liver.

Biallelic mutations in PAH cause phenylketonuria (PKU), one of the most common inborn errors of metabolism. Without treatment, phenylalanine accumulates to toxic levels causing severe intellectual disability and neurological problems. Newborn screening for PKU is universal in developed countries, and early dietary restriction of phenylalanine prevents these complications. BH4 supplementation helps some patients.

Understanding your PAH genetic status provides information about carrier status for PKU. This is particularly important for family planning, as approximately 1 in 50 people are carriers. Affected infants identified through newborn screening require lifelong dietary management to prevent developmental harm.

NutraHacker Raw DNA Analysis Products that include this gene

• Carrier Status Report

Upload raw DNA data to get your very own analysis of gene PAH through your personalized DNA reports.