Park L K, Brainard M A, Dightman D A, Winans G A
National Marine Fisheries Service, Northwest Fisheries Science Center, Seattle, WA 98112.
Mol Mar Biol Biotechnol. 1993 Dec;2(6):362-70.
A total of 798 individuals from 42 different populations of chum salmon (Oncorhynchus keta) were examined for mtDNA variation. Populations were sampled across the geographic range of the species, from mainland Japan around the Pacific Rim to the state of Washington in the United States. The entire D-loop region (approximately 1 kb) was sequenced for 16 individuals from representative populations. Subregions (approximately 200 nucleotides each) of the D-loop reported to be rapidly evolving in salmon were sequenced for another 29 individuals. Only 4 nucleotide variants were detected, and they occurred in only 4 individuals. Four coding regions of the mtDNA genome were also examined using restriction fragment analysis of products amplified via the polymerase chain reaction. Only one, the region coding for NADH dehydrogenase subunits 5 and 6, showed any variation at this level. The restriction enzyme AseI revealed a polymorphism where the frequency of haplotypes was correlated geographically. We surveyed all individuals for this polymorphism and documented a cline in frequency of the haplotypes around the Pacific Rim. There was a significant frequency difference between Japan and 3 other major geographic regions (Russia, Alaska/Yukon, and British Columbia/Washington) for the presence of the 2 haplotypes. This marker may prove useful in the identification of continent-of-origin for individual chum salmon caught in the open ocean.
对来自42个不同种群的798条大麻哈鱼（Oncorhynchus keta）个体进行了线粒体DNA（mtDNA）变异检测。这些种群取自该物种的整个地理分布范围，从日本本土沿太平洋沿岸到美国华盛顿州。对来自代表性种群的16个个体的整个D环区域（约1 kb）进行了测序。对另外29个个体的D环中据报道在鲑鱼中快速进化的亚区域（每个约200个核苷酸）进行了测序。仅检测到4个核苷酸变异，且仅发生在4个个体中。还通过聚合酶链反应扩增产物的限制性片段分析对mtDNA基因组的四个编码区域进行了检测。只有一个区域，即编码NADH脱氢酶亚基5和6的区域，在此水平上显示出任何变异。限制性内切酶AseI揭示了一种多态性，其中单倍型频率与地理分布相关。我们对所有个体进行了这种多态性检测，并记录了环太平洋地区单倍型频率的渐变情况。对于这两种单倍型的存在，日本与其他3个主要地理区域（俄罗斯、阿拉斯加/育空地区和不列颠哥伦比亚省/华盛顿州）之间存在显著的频率差异。这种标记物可能在识别在公海捕获的个体大麻哈鱼的原产大陆方面证明是有用的。
