Question

The best example for pleiotropy is :

(1) ABO Blood group

(2) Skin colour

(3) Phenylketoneuria

(4) Colour Blindness

Answer 1

Answer (3) Phenylketoneuria

Sol. Pleiotropic gene can exhibit multiple phenotypic expression.

An example of this is the disease phenylketonuria.

ABO blood group – Multiple allelism

Skin colour – Shows polygenic inheritance

Colour blindness – Mendelian disorder