noun, plural: base substitutions
This type of mutation occurring in noncoding sequences often does not result in an altered amino acid sequence during translation. If such mutation occurs in the promoter sequence of a gene, the effect may be apparent since the expression of the gene may result in a change in structure and function of the protein product.
Depending on the type of nitrogenous base involved, this type of mutation may be categorized as:
See also: point mutation