鲤鲂杂交形成新型鲫品系的遗传特性研究

鲤（2n=100, ♀）与团头鲂（2n=48, ♂）亚科间远缘杂交形成了同源二倍体类鲫（2n=100）这一新型二倍体同倍体鱼，该鱼在表型、繁殖特性、核DNA、线粒体全基因组、转录组等水平均与自然界中的野生鲫（2n=100）有着很高的相似度，而相对于其父母本而言发生了显著变异。目前该新型鲫经过连续传代已经形成了一个遗传稳定的品系（F1-F4）（2n=100）。鲤鲂杂交途径形成鲫，其遗传变异演化机制是怎样的，尚不清楚。本项目拟通过FISH、微卫星、线粒体基因组测序、转录组测序等遗传学方法进一步对同源二倍体类鲫初期世代的遗传变异情况进行系统研究，拟通过甲基化敏感扩增多态性（MSAP）等表观遗传学方法研究同源二倍体类鲫初期世代的表观遗传变异规律，为远缘杂交形成的二倍体同倍体杂交鱼品系提供遗传学和表观遗传学方面的重要数据。本研究在鱼类遗传育种和生物进化方面具有重要意义。

A new diploid homoploid fish with crucian carp-like homodiploid fish (2n = 100) was formed by distant hybridization between subfamilies with common carp (2n = 100, ♀) and blunt snout bream (2n = 48, ♂). In the phenotype, reproductive characteristics, nuclear DNA, mitochondrial genome, and transcriptome level, the crucian carp-like homodiploid fish were found to be very similar to those of the existing wild crucian carp (2n = 100) in nature, but with significant variation relative to their parents. At present, the new type of crucian carp has formed a genetically stable lineage (F1-F4) (2n = 100) after continuous passage. The crossing of common carp and blunt snout bream can generate crucian carp，but the genetic variation and evolutionary mechanism is not clear. This project intends to systematically study the genetic variation of the early generation of crucian carp-like homodiploid fish through genetic methods such as FISH, microsatellites, mitochondrial genome sequencing and transcriptome sequencing. This project intends to through the epigenetic methods such as methylation-sensitive amplified polymorphism (MSAP) to study the epigenetic variation of the early generation of crucian carp-like homodiploid fish. It provides important data for the genetics and epigenetics of the diploid homoploid hybrid fish lineage formed by distant hybridization. This study is of great significance in fish genetic breeding and biological evolution.