The ghost of hybrids past: fixation of arctic charr (Salvelinus alpinus) mitochondrial DNA in an introgressed population of lake trout (S. namaycush)
The ghost of hybrids past: fixation of arctic charr (Salvelinus alpinus) mitochondrial DNA in an introgressed population of lake trout (S. namaycush)
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DOI：
10.1046/j.1365-294x.1998.00302.x
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发表时间：
1998-01
影响因子：
4.9
通讯作者：
C. Wilson;L. Bernatchez
中科院分区：
文献类型：
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作者：
C. Wilson;L. Bernatchez
研究发现，北极鲑（Salvelinus alpinus）线粒体DNA （mtDNA）完全固定在南曲海鳟（S. namaycush）种群中。这个渐渗种群在湖鳟形态和三个物种诊断微卫星位点方面表现正常。北极炭没有出现在该地区，这表明杂交事件是史前发生的。在几种可能的假设中，对这一异常种群最合理的解释是，在冰川消退后不久，杂交发生在原位，与湖鳟鱼反复回交。尽管来自该地区类似的小河鳟鱼（S. fontinalis）种群的间接证据和数据表明，可能参与了有利于S. alpinus线粒体类型和/或相关核基因的选择，但S. alpinus mtDNA在种群中的固定可能是偶然（漂移）或选择发生的。
Complete fixation of arctic charr (Salvelinus alpinus) mitochondrial DNA (mtDNA) was observed in a southern Québec population of lake trout (S. namaycush). This introgressed population otherwise appeared to be normal with regard to lake trout morphology and three species‐diagnostic microsatellite loci. Arctic charr do not occur in the area, suggesting that the hybridization event was prehistoric. Of several possible hypotheses, the most plausible explanation for this aberrant population is that hybridization occurred in situ soon after deglaciation, with repeated backcrossing of hybrids with lake trout. Fixation of S. alpinus mtDNA in the population may have occurred either by chance (drift) or selection, although indirect evidence and data from similarly introgressed brook trout (S. fontinalis) populations in the region suggest that selection favouring the S. alpinus mitochondrial type and/or associated nuclear genes may have been involved.