Kendon and Sharice just had a baby who was diagnosed with phenylketonuria. Describe this disorder. How can Kendon and Sharice ensure that their son will not develop permanent intellectual disability?

Phenylketonuria is a disorder that prevents the body from producing an enzyme that breaks down phenylalanine, an amino acid, from proteins. The phenylalanine builds up quickly to toxic levels that damage the central nervous system, contributing to mental retardation by 1 year of age. However, permanent damage is not inevitable. Infants who are placed on a strict diet low in phenylalanine (which must continue throughout the childhood into adolescence and adulthood) usually attain average or near-average levels of intelligence.