What are the different types of genetic mutations? Please define each.

Answer 1

Point mutation: one incorrect base is incorporated into the DNA codon sequence. There are three types of point mutations.

1) Silent mutation: incorrect base in codon does not result in a change in the paired amino acid due to redundancy in the genetic code (several anticodons to one amino acid).

2) Nonsense mutation: incorrect base in codon results in a stop codon, stopping the elongating polypeptide chain.

3) Missense mutation: incorrect base in codon results in a different amino acid on the elongating polypeptide chain than was intended by the genetic code (DNA template).

Frameshift Mutation: This is when there is an indel (incorporation or deletion of a base causing a shifting of the down stream codons in the genetic code. For example if the code reads: TAAGTTAA and then there is a deletion of the G base, it will now read TAATTAA. Therefore instead of codon GTT, it will now be TTA, and every other codon after will be changed as well.