6种蟹类DNA条形码鉴定技术研究

摘要

[ Odjective] To study DNA barcode of crab. [ Method] PCR technique was used to amplify the mtDNA COI gene in six crabs spe-cies collected from Zhejiang coastal sea, obtaining 688 bp gene fragment. [ Result] Seven individuals of Portunus sanguinolentus were tested for five haplotypes, five haplotypes were detected in five C. acuta samples, and the haplotypes of C. feriatus, C . japonica, D. dehaani, P. tri-tuberculatus were 3, 2, 2 and 1. The average content of 6 species of COI gene T, C, A and G of crabs was 25. 3％, 18. 2％, 36. 2％ and 20. 3％,A + T was 58. 5％ -64. 1％. The variation of the species was just a little, the genetic distance was 0. 000-0. 004, the range of ge-netic distance was 0. 149-0. 241. Phylogenetic tree using maximum likelihood method revealed that the same species of species firstly cluster, and there was no individual cross-clustering of individual species. [ Conclusion] The analysis indicated that the primer pair of COI-L1490/H2198 for crabs had universal applicability in the barcode study. mtDNA COI gene could be used as a DNA barcode of 6 crabs, with higher distinguish degree supporting the morphological classification.%[目的]研究蟹类DNA条形码技术.[方法]利用PCR技术对浙江沿海6种常见蟹类(n=34)mtDNA COI基因进行扩增,最终获得688 bp基因片段.[结果]7个红星梭子蟹(Portunus sanguinolentus)样品中检测出5个单倍型,5个锐齿蟳(Charybdis acuta)样品中检测出5个单倍型,锈斑蟳(C.feriatus)、日本蟳(C.japonica)、绵蟹(Dromia dehaani)、三疣梭子蟹(P.trituberculatus)样品中检测出单倍型数分别为3、2、2、1;6种蟹类COI基因T、C、A、G的平均含量分别为25.3％、18.2％、36.2％和20.3％,A+T含量为58.5％ ～64.1％;种内变异较小,遗传距离处于0.000～0.004,种间遗传距离为0.143～0.235;使用最大似然法构建的分子进化树揭示相同物种个体首先聚类,不存在不同物种个体交叉聚类.[结论]COI-L1490/H2198通用引物在蟹类条形码研究中具有普遍适用性,mtDNA COI基因能够作为6种蟹类有效鉴别的DNA条形码,且区分度高、支持形态学分类结果.