Liu Ya, Chen Yeyu, Gong Quan, Lai Jiansheng, Du Jun, Deng Xiaochuan
The Fishery Institute of the Sichuan Academy of Agricultural Sciences, Chengdu, China.
PLoS One. 2017 Sep 27;12(9):e0185280. doi: 10.1371/journal.pone.0185280. eCollection 2017.
Acipenser dabryanus is listed as a Critical Endangered species in the IUCN Red List and the first class protected animals in China. Fortunately, A. dabryanus specimens are being successfully bred in captivity for conservation. However, for effective ex situ conservation, we should be aware of the genetic diversity and the degree of relatedness of the individuals selected for breeding. In this study, we aimed at the development of novel and reliable microsatellites used for the genetic study of A. dabryanus. A total of 14,321 simple sequence repeats (SSRs) were detected by transcriptome sequencing and screening. We selected 20 novel and polymorphic microsatellites (non-dinucleotide) with good repeatability from the 100 tested loci for a subsequent genetic and paternity study. A set of captive broodstock (F1 stock, n = 43) and their offspring (F2 stock, n = 96) were used to examine the efficiency of the 20 SSRs for assigning parentage to offspring, with an allocation success of 91.7%. We also found that only a few families predominantly contributed to the progeny produced by the 43 breeders. In addition, mitochondrial DNA data showed that the captive broodstock (F1 individuals) had an excellent probability of the same lineage, implying that a high level of inbreeding may have occurred in these individuals. Our research provides useful information on genetic diversity and reproductive pattern of A. dabryanus, and the 20 SSRs developed in this study can be applied to the future breeding program to avoid inbreeding for this stock or other related species of Acipenseriformes.
达氏鲟被列入国际自然保护联盟濒危物种红色名录中的极危物种，在中国被列为一级保护动物。幸运的是，达氏鲟标本正在人工饲养条件下成功繁殖以进行保护。然而，为了进行有效的迁地保护，我们应该了解用于繁殖的个体的遗传多样性和亲缘程度。在本研究中，我们旨在开发用于达氏鲟遗传研究的新型可靠微卫星。通过转录组测序和筛选共检测到14321个简单序列重复（SSR）。我们从100个测试位点中选择了20个具有良好重复性的新型多态微卫星（非二核苷酸）用于后续的遗传和亲子鉴定研究。一组圈养亲鱼（F1代，n = 43）及其后代（F2代，n = 96）被用于检验这20个SSR在为后代确定亲本方面的效率，分配成功率为91.7%。我们还发现只有少数几个家族对43个繁殖者产生的后代有主要贡献。此外，线粒体DNA数据显示圈养亲鱼（F1代个体）具有相同谱系的极高可能性，这意味着这些个体可能发生了高度近亲繁殖。我们的研究为达氏鲟的遗传多样性和繁殖模式提供了有用信息，并且本研究中开发的20个SSR可应用于未来的育种计划，以避免该种群或其他相关鲟形目物种的近亲繁殖。
