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All Diseases > Phenylalanine Hydroxylase Deficiency
Phenylalanine Hydroxylase Deficiency (PAH Deficiency)
Alternative Names: Phenylketonuria (PKU)
Disease Category: Phenylketonuria
An inherited disorder characterized by low levels or absence of the enzyme phenylalanine hydroxylase (PAH). When PAH is absent or deficient, the amino acid phenylalanine accumulates within the body, becoming toxic to the brain. When not treated, symptoms include mild to severe intellectual disability, depression, parkinsonism, seizures, and developmental delays.
Research groups studying this disease
Phenylalanine Families and Researchers Exploring Evidence (PHEFREE)View Disease Definition
A collaboration of phenylketonuria (PKU) community members joining together as a national voice and supporting local efforts to raise PKU awareness and drive advocacy and education, while ultimately looking for a cure.