which type of mutations can add genes to a chromsome?

Question

I just need it to be answered. 

Answer 1

Hi Jessica,

 

Mutation by definition do not add genes to a chromosome. The term mutation applies to alteration in existing gene in the chromosome. A mutation might be silent in the sense that a base substitution does not alter the protein sequence of the gene. A mutation would create an altered protein when a base substation or deletion causes frame shift in the protein coding sequence of the gene or if it abolishes a splice site and leads to an aberrant non-functional protein or it creates a premature termination codon and makes a truncated protein. So you see a new protein from the same gene would be created by mutation and that is alteration of a gene or creation of new allele of the gene.

 

In the course of evolution if a new allele increases the survival or fitness of the organism and/or cell then it would be selectively propagated and the original allele would phase out from population. One may consider that as creating a new gene.

 

Hope this helps.