Rapid genomic DNA variation in newly hybridized carp lineages derived from Cyprinus carpio (\u2640)\u2009\xd7\u2009Megalobrama amblycephala (\u2642)

Kaikun Luo,Fangzhou Hu,Yeqing Fu,Xuexue Huang,Wuhui Li,Yude Wang,Shaojun Liu,Shi Wang,Qianhong Gu,Pei Zhou

doi:10.1186/s12863-019-0784-2

Kaikun Luo, Fangzhou Hu + Show 8 more

Open Access

https://doi.org/10.1186/s12863-019-0784-2

Copy DOI

Abstract

BackgroundDistant 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.ResultIn 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.ConclusionsOur 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.

Highlights

Distant hybridization can generate changes in phenotypes and genotypes that lead to the formation of new hybrid lineages with genetic variation
In Cyprinidae, the autotetraploid hybrids, originated from hybridization between red crucian carp (Carassius auratus red var., ♀) × blunt snout bream (Megalobrama amblycephala, ♂), has significantly shortened the age of sexual maturity compared to their allotetraploid parents [12]; the hybrids derived from blunt snout bream (♀) × Bleeker’s yellow tail (Xenocypris davidi Bleeker, ♂) has showed significantly higher growth rate compared to their parents [13]
Molecular organization of the Hox genes sequences The organization of the Hox clusters in Common carp (COC), Blunt snout bream (BSB), IDCF1, improved diploid scattered mirror carp (IDMC)-F1, improved diploid common carp (IDC)-F2-C, IDC-F2-M, and The self-crossed offspring of IDMC-F1 (IDMC-F2) are shown in Tables 1 and 2

Summary

Introduction

Distant hybridization can generate changes in phenotypes and genotypes that lead to the formation of new hybrid lineages with genetic variation. Distant hybridization can generate changes in phenotypes and genotypes, leading to the formation of new hybrid lineages with genetic variation and providing a good experimental model for tracing the changes of genetic and epigenetic levels in the early stage of distant hybridization. These newly established bisexual fertile diploid and tetraploid lineages provide new germplasm resources, which are used to produce improved diploid and triploid varieties by crossing diploid species, respectively [19,20,21,22]

Methods

Results

Discussion

Conclusion