Question

Which of the following are controlled by pleiotropic genes?

• A. Phenylketonuria
• B. Sickle-cell anemia
• C. Shape and size of pea seeds
• D. All of the above

Answer 1

The correct option is D

All of the above

A single gene controls a single phenotype. But quite often one gene may influence more than one phenotypic traits. Such gene is called a pleiotropic gene. One gene causes a number of phenotypic traits. In the pea plant, flower color and seed coat color are controlled by same gene. Seed shape and size of peas are also controlled by the same gene. Genetic disorders such as phenylketonuria and sickle-cell anemia are also examples of pleiotropy.