Gene Mutation And Its Types

What is a Gene Mutation?

A gene mutation can be described as a change or alteration in the sequence of nucleotides in a DNA polymer which is a series of nucleotides joined together. It can be altered in many ways and can have effects on the health of an individual. It can cause genetic disorders depending upon the site at which they occur and whether they can alter functions of essential proteins. While some other mutations could be beneficial, making individuals better adapt to their surroundings.

Types of Mutations

Substitution Mutation

It is a mutation that switches a single chemical letter or base for another. It places the wrong nucleotide in the wrong position. It could result in a silent mutation. In such a mutation, a codon is altered to another that encodes the corresponding amino acid resulting in no change in the protein that is generated or it could alter an amino-acid coding codon to a single halt codon resulting in the formation of an incomplete protein which could be non-functional. Also, it could cause an alteration in a codon to one that encodes another amino acid causing a small change in the protein synthesized.


It causes an alteration in the number of DNA bases in a gene by inserting a piece of DNA. Consequently, the protein produced may not be functional.

See Also: Genes


A change in the number of bases of DNA is caused due to the deletion of a piece of DNA. Any number of nucleotides can be deleted or removed. Small deletions may cause the dismissal of a few base pairs within a gene while larger deletions can discard a whole gene or neighbouring genes producing an alteration in the functions of resulting proteins.

Frameshift Mutation

It occurs when a deletion or addition of DNA bases causes an alteration in the reading frame of a gene. There are three groups of base pairs wherein each code for one amino acid in a reading frame. This type of mutation causes a shift in the organization of these bases and modifies the code for amino acids. Consequently, it results in non-functional proteins. Duplications, deletions and insertions could all be frameshift mutations. Visit BYJU’S to explore more about gene mutations in humans and related topics.

Further Reading:


Leave a Comment

Your email address will not be published. Required fields are marked *