Diseases Studied
The Rare Diseases Clinical Research Network is an NIH-funded research network of 20 active consortia or research groups working to advance treatment for diseases that are rare. Use the search tools on this page to find the diseases we currently study. You can reach out to the indicated consortia or research groups for more information on those diseases and studies underway.
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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
Phenylketonuria
Phenylalanine Families and Researchers Exploring Evidence (PHEFREE)
National PKU Alliance
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.