[特邀报告]减数分裂重组介导的突变和选择作用

减数分裂重组介导的突变和选择作用
特邀报告

报告开始:5月13日 14:40:00 (Asia/Shanghai)

报告时间:20min

所在会议:[S4] 分会场四 [S4-1] 基因表达调控与大分子修饰

摘要
Background: Meiotic recombination is an important source of genetic variation, but how recombination shapes the genome is not clearly understood yet. Objective: Here we investigate the roles of recombination on human genome evolution from two aspects: How does recombination shape single nucleotide polymorphism (SNP)-related genomic variation features? Whether recombination drives genome evolution through a neighbor-dependent mutational bias? Methods: we analyzed the relationship of recombination rate with mutational bias and selection effect at SNP sites derived from 1000 Genomes Project. Results: Our results show that SNP density, Ts/Tv, nucleotide diversity and Tajima's D were positively correlated with recombination rate, while Ka/Ks was negatively correlated with the recombination rate. Moreover, compared with non-coding regions, gene exonic regions have lower nucleotide diversity but higher Tajima's D, suggesting that coding regions are subject to stronger negative selection but have fewer rare alleles. Gene set enrichment analysis of the protein-coding genes with extreme Ka/Ks ratio implicates that under the effect of high recombination rates, the genes involved in cell cycle, RNA processing, and oocyte meiosis are subject to strong negative selection. Our data also support S (G or C) > W (A or T) mutational bias and W>S fixation bias in high recombination regions. In addition, the neighbor-dependent mutational bias was found to be stronger at high recombination regions. Conclusion: Our data suggest that genetic variation patterns, particularly the neighbor-dependent mutational bias at SNP sites in the human genome, are mediated by recombination. Keywords: meiotic recombination, gene conversion, genetic diversity, selection, neighbor-dependent mutational bias
报告人
刘国庆
教授 内蒙古科技大学

刘国庆,博士,教授,内蒙古自治区“草原英才”,内蒙古自治区“321人才工程”二层次人选,内蒙古生物工程学会常务理事,内蒙古生物物理学与生物信息学会理事。刘国庆出生于内蒙古通辽市科左中旗,2004年获得物理学专业学士学位(内蒙古师范大学),2009年获得生物物理学专业博士学位(内蒙古大学),2015年和2019年分别在乔治亚大学和北京大学访学一年。目前任职于内蒙古科技大学,从事生物信息学、生物医学大数据挖掘方面的教学和科学研究,关注减数分裂重组的分子机制、肿瘤代谢重编程、染色质结构模拟等领域。主持国家自然科学基金3项,发表学术论文30余篇,获内蒙古自然科学奖一等奖1项。