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Phenylketonuria

Phenylketonuria (PKU) is an inherited disease that affects body chemistry. Individuals with PKU cannot breakdown a part of protein called phenylalanine, which is present in most foods.  Individuals with PKU have very low levels of an enzyme called phenylalanine hydroxylase (or PAH), which converts phenylalanine to other substances the body needs. Without treatment, phenylalanine builds up in the bloodstream and can cause brain damage and mental retardation.

Symptoms

• Developmental delay
• Mental retardation
• Seizures
• Behavior and psychiatric problems
• Decreased skin and hair pigmentation
• Musty body odor
• Dry skin and/or rash

Causes/Risk Factors

• Family history of PKU
• Northern European or Native American ancestry

Genetic Test/Carrier Screen

The following genetic tests may be appropriate based on your personal and/or family history.

• Carrier testing for parents
  • Blood draw for PAH gene mutations
• Prenatal testing
  • Amniocentesis
  • Chorionic villus sampling (CVS)
• Preimplantation genetic diagnosis

See our pre-conception and prenatal services

Schedule an Appointment

To speak with a board-certified genetic counselor about your risks for this disease:

• Schedule genetic counseling appointment online
• Or call 1-800-975-4819
• Send email

Learn More

March of Dimes

National Library of Medicine Genetics Home Reference

National PKU News

PAHdb Web Site

Support Groups

Children Living with Inherited Metabolic Diseases (CLIMB)

Children's PKU Network

National Society for PKU