A mutation is a change in the DNA sequence of a gene that can alter the resulting protein or RNA molecule. Mutations can have a range of effects, from having no discernible effect to causing severe disease or death. Some common effects of mutations include:
- Silent mutations: These are mutations that do not result in any change in the resulting protein. This can occur because the genetic code is degenerate, meaning that multiple codons can code for the same amino acid.
- Missense mutations: These are mutations that result in a change in one amino acid in the resulting protein. Depending on the location of the amino acid change, this can have a range of effects on the protein’s structure and function.
- Nonsense mutations: These are mutations that result in a premature stop codon in the mRNA sequence, leading to a truncated protein that is usually non-functional.
- Frameshift mutations: These are mutations that result in the insertion or deletion of one or more nucleotides in the DNA sequence, causing a shift in the reading frame of the gene. This can lead to the production of a completely different protein or a non-functional protein.
- Regulatory mutations: These are mutations that occur in non-coding regions of the DNA, such as promoters or enhancers, and can affect the level or timing of gene expression.
Mutations are the ultimate source of genetic variation and play a critical role in evolution by providing the raw material for natural selection to act upon. While most mutations have little to no effect, they can occasionally result in novel adaptations that give an organism a selective advantage in its environment.