Question

Sickle cell anemia is an example of
(a)Epistasis
(b)Codominance
(c)Pleiotropy
(d)Incomplete dominance

Answer 1

Hint: The production of two or more unrelated effects by a single gene resulting in two or more phenotypic characters that are not related. They are multi-functional genes with various characters.

Complete answer:
Pleiotropy is the influence of one gene over multiple phenotypic traits. The gene which exhibits this type of expression is called a pleiotropic gene. It is most commonly seen in the case of sickle cell anemia. The mechanism of pleiotropy was first studied by Hans Gruneberg.

Additional Information: -Sickle cell anemia is a blood disorder that is inherited from parents.
-The shape of the red blood cells changes from oval disc-shaped to a sickle-shaped cell.
-The change in red blood cells leads to the abnormality in the oxygen-carrying protein called hemoglobin.
-The passing of two abnormal copies of the beta-globin gene from each parent will result in this disease.
-These genes are responsible for making hemoglobin and are present in chromosome 11.
-The condition of sickle cell anemia was first described by American physician James B. Herrick in 1910.
-Gene pleiotropy occurs when the gene interacts with various other proteins.
-The experiment on pleiotropic genes was first performed by Gregor Mendel in 1866.
-The term ‘pleiotropy' was first coined by Ludwig Plate in his Festschrift, which was published in 1910.
So, the correct answer is ‘Pleiotropy’.

Note: Epistasis is the process of genetics in which the presence or absence of one gene affects the gene mutation, or one gene masks the effect of another gene. Codominance is the condition in which both the alleles of the same gene from both the parents are present and express themselves. Incomplete dominance is a process in which both the genes present are expressed partially resulting in the appearance of a new phenotype.