Practicing Success

Target Exam

CUET

Subject

Biology

Chapter

Principles of Inheritance and Variation

Question:

Sickle cell anemia is an example of which type of mutation ?

Options:

Insertion

Deletion

Point mutation

None of these

Correct Answer:

Point mutation

Explanation:

Mutation is a phenomenon which results in alteration of DNA sequences and consequently results in changes in the genotype and the phenotype of an organism. In addition to recombination, mutation is another phenomenon that leads to variation in DNA. One DNA helix runs continuously from one end to the other in each chromatid, in a highly supercoiled form. Therefore loss (deletions) or gain (insertion/duplication) of a segment of DNA, result in alteration in chromosomes. Since genes are known to be located on chromosomes, alteration in chromosomes results in abnormalities or aberrations.

Mutation also arise due to change in a single base pair of DNA. This is known as point mutation. A classical example of such a mutation is sickle cell anemia.

Deletions and insertions of base pairs of DNA, causes frame-shift mutations