∞ generated and posted on 2016.12.25 ∞
Change in the base sequence of a genome that reduces the negative consequences of another change in base sequence.
|A Compensatory Mutation is when a change in one gene makes things worse but is followed by another change in a gene which helps to fix things.|
Those negative consequences can be, for example, in terms of Darwinian fitness, with the compensatory mutation thereby representing a beneficial mutation that serves to correct the fitness impact of a detrimental mutation.
Typically this correction is not such that the original genotype is not restored and thus a compensatory mutation usually is not the equivalent of a reversion mutation. Nonetheless, an approximation of the original phenotype often is restored, and particularly so if the compensation is other than strictly in terms of fitness.
Note that if the compensatory mutation is found in a different gene, i.e., as found at a different locus, then the impact of the compensatory mutation represents a form of epistasis. See also pseudoreversion along with reversion mutation.