- Neutral mutation
-
In genetics, a neutral mutation is a mutation that has no effect on fitness. In other words, it is neutral with respect to natural selection.
For example, some mutations in a DNA triplet or codon do not change which amino acid is introduced: this is known as a synonymous substitution. Unless the mutation also has a regulatory effect, synonymous substitutions are usually neutral. Some non-synonymous mutations, i.e. mutations that do change the amino acid, are also neutral: these neutral changes are often to a chemically similar amino acid that works just as well. Such mutations may spread through neutral drift.
Neutral mutations can accumulate over time due to genetic drift or genetic draft. According to the neutral theory of molecular evolution, while the majority of mutations are deleterious, the majority of mutations that go on to become fixed as differences between species are neutral.
Many or even most mutations to noncoding DNA are neutral.
Mutation Mechanisms of mutation. Mutation with respect to structure. Large scale mutationChromosomal translocations · Chromosomal inversionsMutation with respect to overall fitness. Deleterious mutation · Advantageous mutation · Neutral mutation · Nearly neutral mutationReferences
Categories:- Mutation
- Evolutionary biology
- Genetics stubs
Wikimedia Foundation. 2010.