Soft Sweeps II—Molecular Population Genetics of Adaptation from Recurrent Mutation or Migration

摘要: In the classical model of molecular adaptation, a favored allele derives from single mutational origin. This ignores that beneficial alleles can enter population recurrently, either by mutation or migration, during selective phase. this case, descendants several these independent origins may contribute to fixation. As consequence, all ancestral haplotypes are linked any copies will be retained in population, affecting pattern sweep on neutral variation. study, we use analytical calculations based coalescent theory and computer simulations analyze adaptation recurrent migration. Under assumption complete linkage, derive robust approximation for number their distribution sample population. We find so-called "soft sweeps," where multiple appear sample, likely biologically realistic values migration rates.