Roussel Valérie, Van Wormhoudt Alain
EA 229 Geoarchitecture, UBO, Faculté des sciences et techniques, Avenue Le Gorgeu, 29238, Brest cedex 3, France.
Station de Biologie Marine, UMR 7208 BOREA - Muséum National d'Histoire Naturelle, Place de La Croix, BP 225, 29900, Concarneau, France.
Biochem Genet. 2017 Apr;55(2):124-154. doi: 10.1007/s10528-016-9778-1. Epub 2016 Oct 20.
The genetic differentiation among the populations of the European abalone Haliotis tuberculata was investigated using different markers to better understand the evolutionary history and exchanges between populations. Three markers were used: mitochondrial cytochrome oxidase I (COI), the sperm lysin nuclear gene, and eight nuclear microsatellites. These markers present different characteristics concerning mutation rate and inheritance, which provided complementary information about abalone history and gene diversity. Genetic diversity and relationships among subspecies were calculated from a sample of approximately 500 individuals, collected from 17 different locations in the north-eastern Atlantic Ocean, Macaronesia, and Mediterranean Sea. COI marker was used to explore the phylogeny of the species with a network analysis and two phylogenetic methods. The analysis revealed 18 major haplotypes grouped into two distinct clades with a pairwise sequence divergence up to 3.5 %. These clades do not correspond to subspecies but revealed many contacts along Atlantic coast during the Pleistocene interglaciations. The sperm lysin gene analysis separated two different subtaxa: one associated to Macaronesian islands, and the other to all other populations. Moreover, a small population of the northern subtaxon was isolated in the Adriatic Sea-probably before the separation of the two lineages-and evolved independently. Microsatellites were analyzed by different genetics methods, including the Bayesian clustering method and migration patterns analysis. It revealed genetically distinct microsatellite patterns among populations from Mediterranean Sea, Brittany and Normandy, Morocco, and Canary and Balearic islands. Gene flow is asymmetric among the regions; the Azores and the Canary Islands are particularly isolated and have low effective population sizes. Our results support the hypothesis that climate changes since the Pleistocene glaciations have played a major role in the geographic distribution of the European abalone. Traces of these events related to maternal inheritance were shown on COI marker.
为了更好地理解欧洲鲍鱼（Haliotis tuberculata）种群之间的进化历史和交流情况，研究人员使用了不同的标记对其种群的遗传分化进行了调查。研究使用了三种标记：线粒体细胞色素氧化酶I（COI）、精子溶素核基因和八个核微卫星。这些标记在突变率和遗传方面呈现出不同的特征，为鲍鱼的历史和基因多样性提供了互补信息。研究从东北大西洋、马卡罗尼西亚和地中海的17个不同地点采集了约500个个体样本，计算了亚种之间的遗传多样性和关系。COI标记通过网络分析和两种系统发育方法用于探索该物种的系统发育。分析揭示了18种主要单倍型，分为两个不同的分支，两两序列差异高达3.5%。这些分支并不对应于亚种，但揭示了更新世间冰期期间大西洋沿岸的许多接触情况。精子溶素基因分析分离出两个不同的亚类群：一个与马卡罗尼西亚群岛相关，另一个与所有其他种群相关。此外，北部亚类群的一小部分种群在亚得里亚海被隔离——可能在两个谱系分离之前——并独立进化。微卫星通过不同的遗传学方法进行分析，包括贝叶斯聚类方法和迁移模式分析。结果揭示了地中海、布列塔尼和诺曼底、摩洛哥以及加那利群岛和巴利阿里群岛种群之间在遗传上不同的微卫星模式。各区域之间的基因流动是不对称的；亚速尔群岛和加那利群岛特别孤立，有效种群规模较小。我们的结果支持这样的假设，即自更新世冰川作用以来的气候变化在欧洲鲍鱼的地理分布中起了主要作用。与母系遗传相关的这些事件的痕迹在COI标记上有所显示。
