State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
Mol Phylogenet Evol. 2013 Jan;66(1):350-9. doi: 10.1016/j.ympev.2012.10.006. Epub 2012 Oct 23.
Carassius auratus complex is believed to originate from East Eurasia and consist of diploid and triploid forms. Diploid form reproduces sexually, whereas triploid form possesses mixture modes of unisexual gynogenesis and sexual reproduction, which makes it a unique case to study evolutionary issues among vertebrates. In this study, we identified 337 triploid individuals from 386 specimens of Carassius auratus complex sampled from 4 different sites of Xingkai Lake and Suifen River on the northeast Asia transboundary areas of Russia and China, and found that triploids were ubiquitous, whereas diploids existed only in SII site of Suifen River. Triploid males were detected in all surveyed sites, and an unusually high triploid male incidence (23%) was found in the Chinese reach of Suifen River. Then, nuclear and cytoplasmic markers were used to analyze their genetic diversity and phylogenetic relationship. A total of 61 distinct tf alleles and 35 mtDNA CR haplotypes were revealed. Higher genetic diversity and divergence were confirmed in triploids than in diploids, and identical genetic background between triploid males and females was demonstrated. Moreover, evolutionary implications and roles of triploid males were suggested in population proliferation and diversity creation of the triploid form.
金鱼复合种被认为起源于东亚，包括二倍体和三倍体形式。二倍体通过有性繁殖进行繁殖，而三倍体则具有单性雌核生殖和有性繁殖的混合繁殖方式，这使其成为研究脊椎动物进化问题的独特案例。在这项研究中，我们从俄罗斯和中国东北亚跨界地区兴凯湖和绥芬河的 4 个不同地点采集的 386 个金鱼复合种标本中鉴定出 337 个三倍体个体，发现三倍体是普遍存在的，而二倍体仅存在于绥芬河的 SII 点。在所有调查的地点都检测到了三倍体雄性，在中国绥芬河段发现了异常高的三倍体雄性发生率（23%）。然后，使用核和细胞质标记来分析它们的遗传多样性和系统发育关系。总共揭示了 61 个不同的 tf 等位基因和 35 个 mtDNA CR 单倍型。三倍体的遗传多样性和分化程度高于二倍体，并且证实了三倍体雄性和雌性之间具有相同的遗传背景。此外，还提出了三倍体雄性在三倍体种群增殖和多样性创造中的进化意义和作用。
