Abstract:
Meiotic recombination is one of the main sources of genetic variation, a fundamental factor in the evolutionary adaptation of sexual eukaryotes. Yet, the role of variation in recombination rate and other recombination features remains underexplored. In this review, we focus on the sensitivity of recombination rates to different extrinsic and intrinsic factors. We briefly present the empirical evidence for recombination plasticity in response to environmental perturbations and/or poor genetic background and discuss theoretical models developed to explain how such plasticity could have evolved and how it can affect important population characteristics. We highlight a gap between the evidence, which comes mostly from experiments with diploids, and theory, which typically assumes haploid selection. Finally, we formulate open questions whose solving would help to outline conditions favoring recombination plasticity. This will contribute to answering the long-standing question of why sexual recombination exists despite its costs, since plastic recombination may be evolutionary advantageous even in selection regimes rejecting any non-zero constant recombination.
摘要:
减数分裂重组是遗传变异的主要来源之一,性真核生物进化适应的一个基本因素。然而,变异在重组率和其他重组特征中的作用仍未得到充分研究。在这次审查中,我们关注重组率对不同外在和内在因素的敏感性。我们简要介绍了响应环境扰动和/或不良遗传背景的重组可塑性的经验证据,并讨论了为解释这种可塑性如何演变以及如何影响重要种群特征而开发的理论模型。我们强调了证据之间的差距,主要来自二倍体的实验,和理论,通常假定单倍体选择。最后,我们提出了开放的问题,这些问题的解决将有助于概述有利于重组可塑性的条件。这将有助于回答长期存在的问题,即为什么性重组存在,尽管它的成本,因为即使在拒绝任何非零恒定重组的选择方案中,塑性重组也可能是进化有利的。