• Harold Chen
Living reference work entry


Classical phenylketonuria (PKU) is a rare metabolic disorder, resulting from a deficiency of a liver enzyme, phenylalanine hydroxylase. The deficiency of the enzyme leads to elevated phenylalanine (Phe) levels in the blood and various tissues including the brain. The incidence in Caucasians is approximately one in 10,000, giving a heterozygote frequency of one in 50 to one in 70. About one in 15,000 infants is born with PKU in the United States.


Newborn Screening Phenylalanine Hydroxylase Large Neutral Amino Acid Phenylalanine Level Dihydropteridine Reductase 
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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Medical GeneticsShriners Hospitals for ChildrenShreveportUSA
  2. 2.Perinatal and Clinical Genetics, Department of PediatricsLSU Health Sciences CenterShreveportUSA

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