Dipartimento di Biologia, Università di Padova, Padova, Italy.
PLoS One. 2011 Mar 29;6(3):e18249. doi: 10.1371/journal.pone.0018249.
While the current expansion of conservation genetics enables to address more efficiently the management of threatened species, alternative methods for genetic relatedness data analysis in polyploid species are necessary. Within this framework, we present a standardized and simple protocol specifically designed for polyploid species that can facilitate management of genetic diversity, as exemplified by the ex situ conservation program for the tetraploid Adriatic sturgeon Acipenser naccarii. A critically endangered endemic species of the Adriatic Sea tributaries, its persistence is strictly linked to the ex situ conservation of a single captive broodstock currently decimated to about 25 individuals, which represents the last remaining population of Adriatic sturgeon of certain wild origin. The genetic variability of three F1 broodstocks available as future breeders was estimated based on mitochondrial and microsatellite information and compared with the variability of the parental generation. Genetic data showed that the F1 stocks have only retained part of the genetic variation present in the original stock due to the few parent pairs used as founders. This prompts for the urgent improvement of the current F1 stocks by incorporating new founders that better represent the genetic diversity available. Following parental allocation based on band sharing values, we set up a user-friendly tool for selection of candidate breeders according to relatedness between all possible parent-pairs that secures the use of non-related individuals. The approach developed here could also be applied to other endangered tetraploid sturgeon species overexploited for caviar production, particularly in regions lacking proper infrastructure and/or expertise.
虽然目前保护遗传学的扩展使我们能够更有效地解决受威胁物种的管理问题，但对于多倍体物种的遗传相关性数据分析，需要替代方法。在这个框架内，我们提出了一个专门为多倍体物种设计的标准化和简单的方案，该方案可以促进遗传多样性的管理，以体外保存的亚得里亚海鲟 Acipenser naccarii 项目为例。作为亚得里亚海支流的一种极度濒危的特有物种，其生存与单一的人工养殖亲鱼群体的体外保存密切相关，目前该亲鱼群体已减少到约 25 条，这是唯一剩下的具有一定野生起源的亚得里亚海鲟种群。基于线粒体和微卫星信息，对三个可用作未来繁殖者的 F1 亲鱼群体的遗传变异性进行了估计，并与亲本世代的变异性进行了比较。遗传数据分析表明，由于作为创始者使用的亲本对较少，F1 种群仅保留了原始种群中存在的部分遗传变异。这促使我们通过纳入更好地代表现有遗传多样性的新的创始者，紧急改进当前的 F1 种群。根据基于带共享值的亲本分配，我们为根据所有可能的亲本对之间的亲缘关系选择候选繁殖者建立了一个用户友好的工具，以确保使用无亲缘关系的个体。这里开发的方法也可以应用于其他因鱼子酱生产而过度捕捞的濒危四倍体鲟鱼物种，特别是在缺乏适当基础设施和/或专业知识的地区。
