Definition:
Phenylketonuria (PKU) is an inherited disorder in which the body is unable to process phenylalanine, an amino acid found in proteins. Instead of being eliminated from the body, unused phenylalanine builds up in the blood, eventually damaging the brain and causing mental retardation and seizures among other effects. Children with PKU receive the gene from both parents, and need to be on a special diet to severely limit their intake of phenylalanine.
