近日，美国国立卫生研究院R. Daniel Camerini-Otero及其课题组发现，减数分裂重组可反映小鼠和人类生殖系复制的模式。这一研究成果于2021年7月13日在线发表在国际学术期刊《细胞》上。

研究人员表示，遗传重组产生新的特征组合，了解重组如何在基因组上分布是现代遗传学的关键。PRDM9蛋白定义了重组热点；然而，兆碱基尺度重组的形成不依赖于PRDM9。

在减数分裂中，重组之前的单轮DNA复制可以建立这些模式；因此，研究人员设计了一种学习减数复制的方法，包括对复制起源的映射。研究人员发现减数分裂性DNA复制是截然不同的；起始的降低减慢了减数分裂中的复制，重组中亚端粒的增加背后存在一种人类雄性中的独特复制模式。研究人员检测到复制与现代和历史重组之间的稳健相关性，并发现复制起始密度与染色体大小相结合确定了单个染色体的重组潜力。这些研究结果和方法对理解DNA复制、遗传重组和哺乳动物生殖系变异的机制有影响。

附：英文原文

Title: Meiotic recombination mirrors patterns of germline replication in mice and humans

Author: Florencia Pratto, Kevin Brick, Gang Cheng, Kwan-Wood Gabriel Lam, Jeffrey M. Cloutier, Daisy Dahiya, Stephen R. Wellard, Philip W. Jordan, R. Daniel Camerini-Otero

Issue&Volume: 2021-07-13

Abstract: Genetic recombination generates novel trait combinations, and understanding how recombinationis distributed across the genome is key to modern genetics. The PRDM9 protein definesrecombination hotspots; however, megabase-scale recombination patterning is independentof PRDM9. The single round of DNA replication, which precedes recombination in meiosis,may establish these patterns; therefore, we devised an approach to study meiotic replicationthat includes robust and sensitive mapping of replication origins. We find that meioticDNA replication is distinct; reduced origin firing slows replication in meiosis, anda distinctive replication pattern in human males underlies the subtelomeric increasein recombination. We detected a robust correlation between replication and both contemporaryand historical recombination and found that replication origin density coupled withchromosome size determines the recombination potential of individual chromosomes.Our findings and methods have implications for understanding the mechanisms underlyingDNA replication, genetic recombination, and the landscape of mammalian germline variation.

DOI: 10.1016/j.cell.2021.06.025

Source: https://www.cell.com/cell/fulltext/S0092-8674(21)00793-5