Hill-Robertson interference maintained by red queen dynamics favours the evolution of sex

Although it is well established theoretically that selective interference among mutations (Hill-Robertson interference) favours meiotic recombination, genome-wide mean rates of mutation and strengths of selection appear too low to support this as the mechanism favouring recombination in nature. A possible solution to this discrepancy between theory and observation is that selection is at least intermittently very strong due to the antagonistic coevolution between a host and its parasites. The Red Queen theory posits that such coevolution generates fitness epistasis among loci, which generates negative linkage disequilibrium among beneficial mutations, which in turn favours recombination. This theory has received only limited support. However, Red Queen dynamics without epistasis may provide the ecological conditions that maintain strong and frequent selective interference in finite populations that indirectly selects for recombination. This hypothesis is developed here through the simul...

尽管理论界已达成共识，突变间的希尔-罗伯逊干涉（Hill-Robertson interference）会有利于减数分裂重组，但全基因组范围内的平均突变率与平均选择强度似乎过低，无法支撑该机制作为自然界中推动重组演化的选择动因。破解这一理论与观测结果间矛盾的可行方案之一是：宿主与其寄生物之间的拮抗共进化，可使选择压力至少间歇性地达到极强水平。红皇后理论（Red Queen theory）指出，这类共进化会在不同基因座间产生适合度上位性（fitness epistasis），进而在有益突变之间形成负连锁不平衡（negative linkage disequilibrium），从而间接促进重组的演化。该理论目前仅获得了有限的实证支持。不过，不依赖上位性的红皇后动力学，或许能够为有限种群中维持强且频繁的选择干涉提供生态条件，而这类选择干涉又会间接推动重组的演化。本文即通过simul...