The long-term fidelity of pinniped hosts to their natal rookery site suggests the genetic architecture of their Uncinaria spp. hookworms should be strongly structured by host breeding biology. However, historical events affecting host populations may also shape parasite genetic structure. Sequences of the mitochondrial cytochrome c oxidase 1 (COI) gene of 86 Uncinaria lucasi individuals were obtained to assess genetic variation and structure of nematodes from 2 host species (68 hookworms from northern fur seals; 18 hookworms from Steller sea lions) and rookeries from 3 widely separated geographic regions: the western Bering Sea and Sea of Okhotsk, eastern Bering Sea, and the eastern Pacific Ocean. High COI haplotype (h = 0.96-0.98) and nucleotide (π = 0.014) diversity was found. The haplotype network showed a star-shaped pattern with a large number of haplotypes separated by few substitutions. The network did not show separation of U. lucasi by geographic region or host species. Fst values between U. lucasi individuals representing geographic regions showed no differentiation, consistent with the absence of genetic structure. At face value, this lack of genetic structure in U. lucasi suggests high gene flow but could also be explained by recent (post-glacial) population expansions of northern fur seals and their hookworms.

中文翻译：

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寄主钩虫Uncinaria lucasi的宿主种群扩展和遗传结构。

寄托寄主寄居其出生地的长期保真度表明了其Uncinaria spp的遗传结构。钩虫应通过寄主繁殖生物学牢固地构建。但是，影响宿主种群的历史事件也可能影响寄生虫的遗传结构。获得86个卢卡斯钩虫（Uncinaria lucasi）个体的线粒体细胞色素C氧化酶1（COI）基因的序列，以评估2个寄主物种（北部海豹的68个钩虫；斯特勒海狮的18个钩虫）和3个鸟群的线虫的遗传变异和结构。广泛分开的地理区域：白令海西部和鄂霍次克海，白令海东部和东太平洋。发现高的COI单倍型（h = 0.96-0.98）和核苷酸（π= 0.014）多样性。单倍型网络显示了一个星形图案，其中有大量单倍型，几乎没有取代。该网络未显示按地理区域或寄主物种分离的U. lucasi。代表地理区域的美国卢卡斯人之间的Fst值未显示差异，这与缺乏遗传结构一致。从表面上看，U.lucasi中缺乏遗传结构表明基因流动高，但也可以由北部海狗及其钩虫的最近（冰川后）种群扩张来解释。