Genetic Variation in an Experimental Goldfish Derived From Hybridization.
Genetic Variation in an Experimental Goldfish Derived From Hybridization.
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杂交实验金鱼的遗传变异
DOI：
10.3389/fgene.2020.595959
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发表时间：
2020
影响因子：
3.7
通讯作者：
Liu S
中科院分区：
文献类型：
--
作者：
Wang J;He W;Zeng J;Li L;Zhang G;Li T;Xiang C;Chai M;Liu S
由于鉴定原生代（G0）极其困难，各种双尾金鱼品种的共同祖先仍然不清楚。然而，一些作者假设这个祖先可能是鲫鱼（Carassius auratus）。在此之前，我们将红鲫（Carassius auratus♀，RCC）与鲤鱼（Cyprinus carpio♂，CC）进行种间杂交，培育出实验性杂交金鱼（EG）。与亲本中的任何一方不同，EG具有与天然金鱼相似的双尾鳍（Carassius auratus， NG）。EG的遗传特征以及其形成的机制在很大程度上是未知的。在这里，我们确定了与EG双尾表型形成相关的chordin基因的遗传变异：第127个氨基酸的停止密码子突变。此外，SSR基因分型结果表明，6个等位基因中，所有EG等位基因在母本（RCC）中也存在，但父本（CC）特异性等位基因完全缺失。在某些位点上，EG和NG等位基因不同，表明这些形态相似的金鱼在遗传上是不相似的。总之，我们的结果表明，遗传变异和分化有助于杂交后代形态特征的变化。这一遗传变异的分析揭示了NG的共同祖先，以及杂交和人工育种在NG物种形成中的作用。
Owning to the extreme difficulty in identifying the primary generation (G0), the common ancestor of various twin-tail goldfish strains remains unclear. However, several authors have hypothesized that this ancestor may have been the crucian carp (Carassius auratus). Previously, we generated an experimental hybrid goldfish (EG) from the interspecific hybridization of red crucian carp (Carassius auratus ♀, RCC) × common carp (Cyprinus carpio ♂, CC). Unlike either parent, EG possessed twin caudal fins similar to those of natural goldfish (Carassius auratus, NG). The genetic characteristics of EG, as well as the mechanisms underlying its formation, are largely unknown. Here, we identified the genetic variation in the chordin gene that was associated with the formation of the twin-tail phenotype in EG: a stop codon mutation at the 127th amino acid. Furthermore, simple sequence repeat (SSR) genotyping indicated that, among the six alleles, all of the EG alleles were also present in female parent (RCC), but alleles specific to the male parent (CC) were completely lost. At some loci, EG and NG alleles differed, showing that these morphologically similar goldfish were genetically dissimilar. Collectively, our results demonstrated that genetic variations and differentiation contributed to the changes of morphological characteristics in hybrid offspring. This analysis of genetic variation in EG sheds new light on the common ancestor of NG, as well as on the role of hybridization and artificial breeding in NG speciation.