BACKGROUND Distant hybridization can generate changes in phenotypes and genotypes that lead to the formation of new hybrid lineages with genetic variation. In this study, the establishment of two bisexual fertile carp lineages, including the improved diploid common carp (IDC) lineage and the improved diploid scattered mirror carp (IDMC) lineage, from the interspecific hybridization of common carp (Cyprinus carpio, 2n = 100) (♀) × blunt snout bream (Megalobrama amblycephala, 2n = 48) (♂), provided a good platform to investigate the genetic relationship between the parents and their hybrid progenies. RESULT In this study, we investigated the genetic variation of 12 Hox genes in the two types of improved carp lineages derived from common carp (♀) × blunt snout bream (♂). Hox gene clusters were abundant in the first generation of IDC, but most were not stably inherited in the second generation. In contrast, we did not find obvious mutations in Hox genes in the first generation of IDMC, and almost all the Hox gene clusters were stably inherited from the first generation to the second generation of IDMC. Interestingly, we found obvious recombinant clusters of Hox genes in both improved carp lineages, and partially recombinant clusters of Hox genes were stably inherited from the first generation to the second generation in both types of improved carp lineages. On the other hand, some Hox genes were gradually becoming pseudogenes, and some genes were completely pseudogenised in IDC or IDMC. CONCLUSIONS Our results provided important evidence that distant hybridization produces rapid genomic DNA changes that may or may not be stably inherited, providing novel insights into the function of hybridization in the establishment of improved lineages used as new fish resources for aquaculture.

中文翻译：

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鲤鱼（♀）×lo脑Mega（newly）衍生的新杂交鲤鱼谱系的快速基因组DNA变化。

背景技术远距离杂交可以产生表型和基因型的变化，从而导致形成具有遗传变异的新杂交谱系。在这项研究中，通过普通鲤鱼的种间杂交（Cyprinus carpio，2n = 100）建立了两个双性生殖鲤鱼谱系，包括改良的二倍体普通鲤鱼（IDC）谱系和改良的二倍体分散镜鲤（IDMC）谱系。 （♀）×钝鼻鲷（Megalobrama amblycephala，2n = 48）（♂），为研究父母及其杂交后代之间的遗传关系提供了一个很好的平台。结果在这项研究中，我们调查了来自普通鲤鱼（ages）×钝嘴鲷（♂）的两种改良鲤鱼谱系中12种Hox基因的遗传变异。第一代IDC中Hox基因簇丰富，但是大多数人并没有在第二代中稳定地继承下来。相反，我们在第一代IDMC中没有发现Hox基因的明显突变，并且几乎所有的Hox基因簇都从第一代到第二代IDMC稳定地遗传。有趣的是，我们在两个改良鲤鱼谱系中均发现了明显的Hox基因重组簇，并且在第一类至第二代中这两种改良鲤鱼谱系都稳定地继承了Hox基因的部分重组簇。另一方面，一些Hox基因逐渐成为假基因，而某些基因在IDC或IDMC中被完全假基因化。结论我们的研究结果提供了重要的证据，说明远距离杂交会产生快速的基因组DNA变化，这种变化可能会或可能不会被稳定地遗传，