The benefits of recombination:
Recombination makes combinations of alleles across two or more loci that may be advantageous. Especially important with epistasis (interactions between loci) favouring a specific combination of alleles at the two loci.
Recombination helps get rid of bad mutations to create mutation-free offspring.
========================================
Recombination is capable of breaking up advantageous allelic combinations. This results in the theoretical possibility that by increasing the likelihood of disrupting a beneficial haplotype, outbreeding can result in a drop in fitness known as outbreeding depression.
========================================
An allele that rises to high frequency through positive selection at a linked locus is said to be "hitchhiking". The reduction in diversity at loci linked to a recently fixed allele is dubbed as a selective sweep. Conversely, negative selection at a locus also reduces diversity at linked loci, albeit at a slow rate, by a processed known as background selection.
========================================
If we know the recombination rate per generation (r) between the newly mutated locus and a given locus, after a certain number of generations (t) we can track the decay of LD over time, by relating the present value of D (Dt) to the inital value of D (D0) using the equation:
Dt=(1-r)^t X D0
No comments:
Post a Comment