Tranah G, Campton D E, May B
Department of Animal Science, Meyer Hall, University of California-Davis, Davis, CA 95616, USA.
J Hered. 2004 Nov-Dec;95(6):474-80. doi: 10.1093/jhered/esh077.
To determine the genetic origin of individual sturgeon that are morphologically intermediate to pallid (Scaphirhynchus albus) and shovelnose (Scaphirhynchus platorhynchus) sturgeon, we combined previously published mitochondrial DNA (mtDNA) and microsatellite data with additional microsatellite data. Two sympatric populations of pallid and shovelnose sturgeon from the upper Missouri River and a sympatric population containing pallid, shovelnose, and putative pallid-shovelnose hybrids from the Atchafalaya River were analyzed using an index of hybridization and a principle components analysis of individual relatedness scores. The addition of new microsatellite data improved our ability to genetically differentiate individual pallid and shovelnose sturgeon collected in both areas. Our methods distinguished morphologically intermediate Atchafalaya River sturgeon, which appear to be genetically intermediate between pallid and shovelnose sturgeon. The results support a hybrid origin for morphologically intermediate individuals, although it is unclear whether they are all first-generation hybrids or if some are the result of subsequent backcrossing with the more common shovelnose sturgeon.
为了确定在形态上介于浅色鲟（Scaphirhynchus albus）和铲吻鲟（Scaphirhynchus platorhynchus）之间的个体鲟鱼的遗传起源，我们将先前发表的线粒体DNA（mtDNA）和微卫星数据与额外的微卫星数据相结合。利用杂交指数和个体亲缘关系得分的主成分分析，对来自密苏里河上游的两个浅色鲟和铲吻鲟同域种群，以及一个来自阿查法拉亚河、包含浅色鲟、铲吻鲟和假定的浅色鲟 - 铲吻鲟杂交种的同域种群进行了分析。新微卫星数据的加入提高了我们对这两个地区采集的个体浅色鲟和铲吻鲟进行基因区分的能力。我们的方法区分出了形态上介于两者之间的阿查法拉亚河鲟鱼，它们在基因上似乎也介于浅色鲟和铲吻鲟之间。结果支持形态上介于两者之间的个体具有杂交起源，尽管尚不清楚它们是否都是第一代杂交种，或者是否有些是与更常见的铲吻鲟随后回交的结果。
