A pleiotropic gene :
is a gene evolved during Pliocene.
controls a trait only in combination with another gene
controls multiple traits in an individual.
is expressed only in primitive plants.
A pleiotropic gene is one that regulates several phenotypic features in a person. A pleiotropic gene influences metabolic pathways, which result in a variety of phenotypes. Pleiotropism is demonstrated by phenylketonuria. A mutation in the gene that encodes for phenylalanine hydroxylase causes this condition. Phenylketonuria is distinguished by phenotypic characteristics such as skin coloring, hair loss, and mental impairment.