Hitchhiking Under Positive Darwinian Selection

摘要: Positive selection can be inferred from its effect on linked neutral variation. In the restrictive case when there is no recombination, all variation removed. If recombination present but rare, both deterministic and stochastic models of positive show that hitchhikes to either low or high frequencies. While frequency distribution influenced by a number evolutionary processes, an excess derived variants at unique pattern produced hitchhiking (derived refers nonancestral state as determined outgroup). We adopt statistic, H, measure compared intermediate variants. Only few high-frequency are needed detect since not many expected under neutrality. This particular utility in regions where much normal limited small (<1 kb) region. Application H test published surveys Drosophila reveals likely have been selection.