Question

What is gene mutation? Describe the type of gene mutation.

Answer 1

The change or variation occur in the genetic material is called as mutation, it may be good which bring certain good feature for survival and may not be good because alteration if genetic material can cause some kind of genetic disorder which may threatened the life of individual.

Complete answer:
The sudden change in nucleotide sequence of DNA causes gene mutation which is also known as point mutation. The damage in DNA caused by mutation, which is either by substitution, deletion and insertion of the base pair in DNA, altered DNA sequence may lead to the death of the cell or may cause tumor or cancer. Mutated DNA loses its functionality.
Type of mutation:
Deletion, Insertion and Substitution of base.
1. Base substitution:- Replacement of single base is represented by point mutation. Example Glu replaces Val that causes sickle cell anemia disease. It is further two type:-
a. Transition: this type of base substitution mutation represented by when a purine is replaced or substituted by another purine or pyrimidine is replaced by another pyrimidine.
b. Transversion :- this mutation occurs when pyrimidine is replaced by another pyrimidine or vice- versa.
2. Deletion:- It is also known as frameshift mutation, it occurs when one or more base pairs are lost from the DNA. This type of mutated DNA create altered product or non-functional product.
3. Insertion:- The adding of Base pairs may cause frame shifts which depend on the number of base pairs are added or inserted.

Note: The cause of mutation occurs during replication, DNA recombination, Chemical damage in DNA, Influenced by radiations and during DNA repair. Point mutations occur in DNA, they are either silent, missense or nonsense, which are related to the substitution type of mutation.