Recombination and hitchhiking of deleterious alleles.

摘要: When new advantageous alleles arise and spread within a population, deleterious at neighboring loci can hitchhike alongside them to fixation in areas of low recombination, introducing fixed mutation load. We use branching processes diffusion equations calculate the probability that allele hitchhikes fixes an mutant. As expected, hitchhiker rises with selective advantage sweeping declines disadvantage hitchhiker. then computer simulations genome infinite number investigate increase load after mutant is introduced. show appearance on genetic backgrounds loaded has two potential effects: it fix alleles, facilitate persistence recombinant lineages happen occur. The latter expected reduce signals selection surrounding region. consider these results light human data infer how likely such hitchhikers have occurred our recent evolutionary past.