Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, USA.
Dipartimento di Scienze della Vita e dell`Ambiente, Universita` Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona, Italy.
Int J Mol Sci. 2019 Mar 5;20(5):1129. doi: 10.3390/ijms20051129.
In this paper, we used a Genotyping-by-Sequencing (GBS) approach to find and genotype more than 4000 genome-wide SNPs (Single Nucleotide Polymorphisms) from striped killifish exposed to a variety of polychlorinated biphenyls (PCBs) and other aromatic pollutants in New Bedford Harbor (NBH, Massachusetts, USA). The aims of this study were to identify the genetic consequences of exposure to aquatic pollutants and detect genes that may be under selection. Low genetic diversity ( and π) was found in the site exposed to the highest pollution level, but the pattern of genetic diversity did not match the pollution levels. Extensive connectivity was detected among sampling sites, which suggests that balanced gene flow may explain the lack of genetic variation in response to pollution levels. Tests for selection identified 539 candidate outliers, but many of the candidate outliers were not shared among tests. Differences among test results likely reflect different test assumptions and the complex pollutant mixture. Potentially, selectively important loci are associated with 151 SNPs, and enrichment analysis suggests a likely involvement of these genes with pollutants that occur in NBH. This result suggests that selective processes at genes targeted by pollutants may be occurring, even at a small geographical scale, and may allow the local striped killifish to resist the high pollution levels.
在这项研究中，我们使用基于测序的基因分型（GBS）方法，从新贝德福德港（美国马萨诸塞州）暴露于多种多氯联苯（PCBs）和其他芳香族污染物的条纹鲦鱼中发现并基因分型了 4000 多个全基因组 SNPs（单核苷酸多态性）。本研究的目的是确定暴露于水生污染物的遗传后果，并检测可能受到选择的基因。在暴露于最高污染水平的地点发现遗传多样性低（ 和 π），但遗传多样性模式与污染水平不匹配。在采样地点之间检测到广泛的连通性，这表明平衡的基因流可能解释了对污染水平没有遗传变异的原因。选择测试鉴定出 539 个候选异常值，但许多候选异常值在测试之间没有共享。测试结果的差异可能反映了不同的测试假设和复杂的污染物混合物。潜在地，与 151 个 SNP 相关的重要选择位点，富集分析表明这些基因可能与新贝德福德港存在的污染物有关。这一结果表明，即使在小的地理尺度上，污染物靶向基因的选择过程也可能正在发生，并可能使当地的条纹鲦鱼能够抵抗高污染水平。
