Cruaud Astrid, Groussier Géraldine, Genson Guenaëlle, Sauné Laure, Polaszek Andrew, Rasplus Jean-Yves
CBGP, INRA, CIRAD, IRD, Montpellier SupAgro, Univ Montpellier, Montpellier, France.
Institut Sophia Agrobiotech, INRA, CNRS, Université Côte d'Azur, Sophia Antipolis, France.
PeerJ. 2018 Oct 16;6:e5640. doi: 10.7717/peerj.5640. eCollection 2018.
A major obstacle to high-throughput genotyping of microhymenoptera is their small size. As species are difficult to discriminate, and because complexes may exist, the sequencing of a pool of specimens is hazardous. Thus, one should be able to sequence pangenomic markers (e.g., RADtags) from a single specimen. To date, whole genome amplification (WGA) prior to library construction is still a necessity as at most 10 ng of DNA can be obtained from single specimens (sometimes less). However, this amount of DNA is not compatible with manufacturer's requirements for commercial kits. Here we test the accuracy of the GenomiPhi kit V2 on wasps by comparing RAD libraries obtained from the WGA of single specimens (F0 and F1 generation, about1 ng input DNA for the WGA (0.17-2.9 ng)) and a biological amplification of genomic material (the pool of the progeny of the F1 generation). Globally, we found that 99% of the examined loci (up to 48,189 for one of the crosses, 109 bp each) were compatible with the mode of reproduction of the studied model (haplodiploidy) and Mendelian inheritance of alleles. The remaining 1% (0.01% of the analysed nucleotides) could represent WGA bias or other experimental/analytical bias. This study shows that the multiple displacement amplification method on which the GenomiPhi kit relies, could also be of great help for the high-throughput genotyping of microhymenoptera used for biological control, or other organisms from which only a very small amount of DNA can be extracted, such as human disease vectors (e.g., sandflies, fleas, ticks etc.).
膜翅目小昆虫高通量基因分型的一个主要障碍是它们体型微小。由于物种难以区分,且可能存在复合种群,对一批样本进行测序存在风险。因此,应该能够从单个样本中对泛基因组标记(例如RAD标签)进行测序。迄今为止,在构建文库之前进行全基因组扩增(WGA)仍然是必要的,因为从单个样本中最多只能获得10 ng的DNA(有时更少)。然而,这个DNA量与商业试剂盒制造商的要求不兼容。在这里,我们通过比较从单个样本(F0和F1代,WGA输入DNA约1 ng(0.17 - 2.9 ng))的WGA获得的RAD文库以及基因组材料的生物扩增(F1代后代的混合样本),来测试GenomiPhi试剂盒V2在黄蜂上的准确性。总体而言,我们发现99%的检测位点(其中一个杂交组合多达48,189个,每个位点109 bp)与所研究模型的繁殖模式(单双倍体)和等位基因的孟德尔遗传相符合。其余1%(占分析核苷酸的0.01%)可能代表WGA偏差或其他实验/分析偏差。这项研究表明,GenomiPhi试剂盒所依赖的多重置换扩增方法,对于用于生物防治的膜翅目小昆虫或其他只能提取极少量DNA的生物(如人类疾病传播媒介,例如白蛉、跳蚤、蜱等)的高通量基因分型也可能有很大帮助。