AP BIOLOGY

Detailed explanation-1: -It is an inherited disorder that that can cause intellectual and developmental disabilities (IDDs) if not treated. In PKU, the body can’t process a portion of a protein called phenylalanine (pronounced fen-l-AL-uh-neen), which is in all foods containing protein. High levels of phenylalanine can cause brain damage.

Detailed explanation-2: -Severe intellectual disabilities and other problems associated with PKU can be prevented by early diagnosis and proper diet control. The success of diet control requires the cooperation of everyone who comes in contact with the child.

Detailed explanation-3: -Classical PKU is an autosomal recessive disorder, caused by mutations in both alleles of the gene for phenylalanine hydroxylase (PAH), found on chromosome 12. In the body, phenylalanine hydroxylase converts the amino acid phenylalanine to tyrosine, another amino acid.

Detailed explanation-4: -Phenylketonuria (PKU) is an autosomal recessive metabolic genetic disorder characterized by a mutation in the gene for the hepatic enzyme phenylalanine hydroxylase (PAH), rendering it nonfunctional. Other non-PAH mutations can also cause PKU. This is an example of non-allelic genetic heterogeneity.