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phenylketonuria
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Phenylketonuria Figure 4: Enzyme defects in disorders of the amino acids phenylalanine and tyrosine. family pedigree
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Phenylketonuria
Phenylketonuria The blood of a two-week-old infant is collected for a phenylketonuria screening.

phenylketonuria

genetic metabolic disease
Also known as: PKU, phenylpyruvic oligophrenia
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phenylketonuria (PKU), hereditary inability of the body to metabolize the amino acid phenylalanine. Phenylalanine is normally converted in the human body to tyrosine, another amino acid, by a specific organic catalyst, or enzyme, called phenylalanine hydroxylase. This enzyme is not active in individuals who have phenylketonuria. As a result of this metabolic block, abnormally high levels of phenylalanine accumulate in the blood, cerebrospinal fluid, and urine. Abnormal products of phenylalanine breakdown, such as highly reactive...

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