Question

is it true or false;

Any deletion mutation in the coding sequence of a proton will result in a protein sequence change

Answer 1

A mutation refers to a change in the sequence of the DNA. The mutations are of two main types:

1. Point Mutations: These refer to a change in the single base pair in the DNA. There are three types of point mutations. These are:

a) Silent Mutations: These point mutations result in a change in the DNA sequence. However, this change is not translated to the amino acid code. As a result, the mutation will not affect the peptide sequence.

b) Missense Mutations: These point mutations result in a change in the DNA sequence and also result in the change in the amino acid it codes for. As a result, there is a change in the peptide sequence at the single amino acid level.

c) Nonsense Mutations: These point mutations result in changing a codon to a stop codon. As a result, no amino acid is incorporated at the position and instead, the peptide length shortens.

2. Frameshift Mutations: These mutations result in changing the reading frame of the DNA template. There are two types of mutations that can lead to this:

a) Addition Mutations: Here, new bases are added to the original sequence. If the number of bases that are added is not multiples of 3, then this changes the reading frame resulting in a complete change of peptide sequence.

b) Deletion Mutations: Here, one or more bases are deleted from the original sequence. If the number of bases that are deleted are not multiples of 3, then this changes the reading frame resulting in a complete change of peptide sequence.

Hence, as is clear from the description, the deletion mutation need not always result in a change in the frame. This happens only when the deletion involves the removal of non-multiple of 3 bases.

Therefore, the statement is FALSE.