长鳍吻鮈(Rhinogobio ventralis Sauvage et Dabry)，隶属鲤科、鮈亚科、吻鮈属，主要分布于长江上游干流、乌江下游以及岷江、沱江、嘉陵江等水系，是一种具有重要经济价值的长江上游特有鱼类。上世纪90年代以来，过度捕捞、水域污染、生境破坏、水利工程建设等人类活动，使得长鳍吻鮈的种群数量显著减少，长江上游梯级开发中规划或正在兴建的多座大型水利工程，小南海水电站，乌江银盘、彭水水电站等，其叠加的累积效应可能会对河流生态系统的水域环境产生较大改变，对长江上游特有鱼类的物种生存产生重大影响。特别对于长鳍吻鮈这类适应流水生活、产漂流性卵的鱼类，急流生境的破坏导致产卵场的丧失，对其生存和繁殖将产生更为严重的影响。为了更有效的保护和合理利用鱼类资源，利用DNA分子标记对长鳍吻鮈进行群体遗传学研究，摸清其种群遗传结构和遗传多样性水平，对于其物种生存有着重要现实意义。
Rhinogobio ventralis, belonging to subfamily Gobioninea of Cyprinidae, distributed mainly in the upper reaches of the Yangtze River, the lower reaches of the Wujiang River, as well as the Minjiang River, the Tuojiang River and the Chia-ling River. It is an endemic species of great economic importance. Since 1990s, overfishing, water pollution, habitat destruction and construction of hydropower projects have led to decline of Rhinogobio ventralis population. Many hydropower stations were built or at various stages of planning and design for series development at upper reaches of the Yangtze River，such as Xiaonanhai hydropower station in Chongqing, Yinpan and Pengshui hydropower stations on the Wujiang River. The consequent progressive effect of them will greatly change the biosystem of the rivers, therefore make an irretrievable impact on endemic fishes in the upper reaches of the Yangtze River. Especially for fishes living in rushing water and spawning pelagic eggs like Rhinogobio ventralis, reduction of spawning ground caused by habitat destruction after water power plant construction will have a greater impact on its existence and reproduction. For effective conservation and reasonable exploitation of this species, population genetic studies based on DNA markers, in order to ascertain genetic structure and genetic diversity of the population, are of great significance for existence of this species.
In this study, from an (AAAG)n enriched genomic library, we obtained 61 microsatellite DNA sequences out of 172 positive clones. According to these sequences, we designed 31 PCR primers, 25 of which could produce valid PCR products in Rhinogobio ventralis individuals and twelve loci exhibited polymorphic.
Preliminary studies were carried out on a 40-individual population of Rhinogobio ventralis from Chongqing section of the Yangtze River. Twelve polymorphic loci have two to 11 alleles (average = 6.3) per locus. Observed heterozygosities and expect heterozygosities ranged from 0.15 to 0.88 (average = 0.58) and 0.18 to 0.85 (average = 0.68), respectively. Nine loci were highly informative (PIC>0.5), two were reasonably informative (0.25