• Entry
  • Reader's guide
  • Entries A-Z
  • Subject index

Phenylketonuria

  • By: Karen T. Carey
  • In: Encyclopedia of School Psychology
  • Edited by: Steven W. Lee
  • Subject:School/Educational Psychology (general), School Psychology, Educational Psychology

Phenylketonuria (PKU) is a rare, inborn metabolism error resulting from a deficiency of phenylalanine hydroxylase (an enzyme) transmitted by an autosomal (i.e., nonsex chromosome) recessive gene. The incidence of PKU in the United States is approximately 1:15,000, and 1 in 60 persons (generally mothers) is a carrier of the gene.

The most serious outcomes of PKU are moderate to severe mental retardation and behaviors such as hyperactivity, inattention, perceptual–motor problems, aggressiveness, negative mood, and motor difficulties. Children untreated for PKU are normal at birth, but begin to show slowed brain development by four months.

Well-established screening procedures (via blood analysis) are used to test every child for PKU at birth. Managing the disorder via dietary supplements from the first month of life can result in normal development. ...

    • Loading...
    locked icon

    Sign in to access this content

    Get a 30 day FREE TRIAL

    • Watch videos from a variety of sources bringing classroom topics to life
    • Read modern, diverse business cases
    • Explore hundreds of books and reference titles