Oliver C, Hollingsworth P M, Gornall R J
Genetics and Conservation, Royal Botanic Garden, 20A Inverleith Row, Edinburgh EH3 5LR, UK.
Heredity (Edinb). 2006 Mar;96(3):222-31. doi: 10.1038/sj.hdy.6800785.
The genetic structure of populations of an arctic-montane herb, Saxifraga hirculus (Saxifragaceae), was analysed by means of chloroplast restriction fragment-length polymorphism. Sampled populations were distributed across Europe and North America (Alaska and Colorado). There was no evidence for geographically structured genetically divergent lineages, and although no haplotypes were shared between North America and Europe, the haplotypes from different continents were intermixed on a minimum spanning tree. European populations were much more highly differentiated and had much lower levels of haplotype diversity than their Alaskan counterparts. Centres of haplotype diversity were concentrated in those Alaskan populations located outside the limits of the last (Wisconsin) glaciation, suggesting that they may have acted as refugia during the Pleistocene. It was not possible to identify putative migration routes or corresponding refugia in the European genepool. One British population, from the Pentland Hills, was genetically very distant from all the others, for reasons that are as yet unknown.
通过叶绿体限制性片段长度多态性分析了北极山地草本植物圆叶虎耳草（虎耳草科）种群的遗传结构。采样种群分布在欧洲和北美（阿拉斯加和科罗拉多）。没有证据表明存在地理结构上的遗传分化谱系，尽管北美和欧洲之间没有共享单倍型，但来自不同大陆的单倍型在最小生成树上相互混杂。欧洲种群的分化程度更高，单倍型多样性水平比阿拉斯加的对应种群低得多。单倍型多样性中心集中在阿拉斯加那些位于末次（威斯康星）冰川界限之外的种群中，这表明它们可能在更新世期间充当了避难所。在欧洲基因库中无法确定假定的迁移路线或相应的避难所。来自彭特兰山的一个英国种群在遗传上与所有其他种群非常遥远，原因尚不清楚。
