NEET Class neet Answered

The mutation which alter the entire reading frame of the message are called framneshift mutations. These include deletions and insertions of nitrogenous bases. If the number of bases inserted or deleted is not divisible by 3, all the base triplets beyond the site of the mutation are altered. This changes the genetic code and results in the formation of an entirely new polypeptide.

However, it is possible that the reading frame remains unaltered only if it is a same sense mutation. A same sense mutation changes a codon which does not altrr the amino acid of a polypeptide. For example: GCA to GCT, arginine is formed in either case.