Question

Explain how pleiotropy (a non-Mendelian characteristic) affects the human genetic disorder PKU (Phenylketonuria) have? show proof.

Answer 1

Pleiotropy is a greek word meaning Pleon- more and tropos -way.

That means single gene responsible for than one traits or disorders.

Phenylketonuria(PKU) is an autosomal recessive metabolic genetic disorder characterized by mutation in the enzyme Phenylalanine hydroxylase(PAH).

A defect in the single gene that codes for PAH enzyme leads to PKU causing mental retardation, eczema, mousy odour, lighter pigmentation etc.

Phenylalanine is one of the most important amino acid which we intake from our diet. PAH helps in breaking Phenylalanine into tyrosine, in the absence of PAH, this phenyalanine converted into phenylketone and other derivatives.