Pearson C V M, Rogers A D, Sheader M
School of Ocean and Earth Science, University of Southampton, Southampton Oceanography Centre, European Way, Southampton, SO14 3ZH.
Mol Ecol. 2002 Nov;11(11):2285-93. doi: 10.1046/j.1365-294x.2002.01621.x.
The sea anemone Nematostella vectensis occurs in lagoons in the United States and along the southern and eastern coasts of the United Kingdom. In the United Kingdom it is considered rare and is threatened, principally through the destruction of lagoonal habitat. Random amplified polymorphic DNA (RAPD) data from populations across most of the rane of N. vectensis in the United Kingdom revealed that 61% of individuals had an identical genotype, the frequency of which varied from 0.01 to 1.00. These data provide strong evidence for predominantly clonal reproduction and for the existence of a 'general-purpose genotype' in the UK populations. Alternatively, the low levels of genetic variation observed in some N. vectensis populations may have resulted if they were founded from very few successful individuals from the United States. Analysis of molecular variance (amova) showed significant genetic differentiation between lagoons with no large-scale pattern of geographical variation. This result is consistent with occasional passive or anthropogenic dispersal of low numbers of individuals between lagoons followed by asexual proliferation of immigrants. Transplantation of individuals of the predominant (general-purpose) genotype, for conservation purposes, will probably stand a good chance of survival given its prevalence throughout the United Kingdom.
海葵星状海葵分布于美国的泻湖以及英国南部和东部沿海地区。在英国，它被视为珍稀物种且受到威胁，主要原因是泻湖栖息地遭到破坏。对英国星状海葵分布范围内大多数种群的随机扩增多态性DNA（RAPD）数据显示，61%的个体具有相同的基因型，其频率在0.01至1.00之间变化。这些数据为英国种群中主要的克隆繁殖以及“通用基因型”的存在提供了有力证据。另外，如果某些星状海葵种群是由来自美国的极少数成功个体建立起来的，那么观察到的低水平遗传变异可能就是由此导致的。分子方差分析（AMOVA）表明，泻湖之间存在显著的遗传分化，且没有大规模的地理变异模式。这一结果与偶尔少量个体通过被动或人为方式在泻湖之间扩散，随后移民进行无性繁殖的情况相一致。出于保护目的，移植占主导地位（通用）基因型的个体，鉴于其在英国各地的普遍存在，可能很有存活的机会。
