目的 通过分析16S rDNA 551bp基因序列,鉴定常见嗜尸性蝇类种属.方法 随机采集17个地区放置于室外草地的家兔尸体上7个种24只嗜尸性苍蝇样本,经形态学鉴定种类后,提取胸肌DNA,对16S rDNA 551bp基因片段进行PCR扩增,产物纯化、测序后上传GenBank；利用MEGA 4.0软件构建序列间的系统发育树,分析建立种内及种间进化分歧表.结果 24只样本16S rDNA序列分析显示7种蝇类可以较好聚类；其中棕尾别麻蝇种内进化分歧整体均数为2.8％,家蝇为1.5％,丽蝇科的5个种均在0.7％以内.上述7个蝇种的种间进化分歧均数在1.6％ ～7.1％之间.其中,棕尾别麻蝇、家蝇与其它蝇类的种间分歧均数在4.0％ ～7.1％之间.结论 本文分析结果显示,蝇种间同源性相差明显,采用mtDNA 16S rDNA中551bp基因序列分析,可进行蝇种鉴定.%Objective Identifing species of Sarcosaphagous flies by analyzing the amplified 551bp of 16S rDNA. Methods Twenty-four Samples of sarcossphagous flies belong to seven species on the corpses of rabbits were collected from seventeen districts. All samples were identified by entomologists using traditional morphological characteristics and then the Mitochondrial DNA of flies was extracted using the phenol chloroform extraction. Polymerase chain reactions were conducted on a Perkin-Elmer 9600 thermal cycler. PCR products were purified using Nucleic Acid Purification Kit. The PCR products were sequenced and the obtained sequences have been deposited in CenBank by Sequin. A neighbour-joining tree using the Tamura and Nei model of nucleotide substitution was constructed using the MEGA 4. 0 package. Results The 551 bp 16S rDNA fragment was successfully sequenced for all the specimens. All flies were rightly assigned into seven species with monophyletic separation in the N-J tree. The intraspecific and interspecific variation analyze showed 0 ~ 2. 8% sequence divergence within species and 1. 6% ~ 7. 1% divergence between species. Conclusion From the bootstrap support for each group and the level of nucleotide divergence between groups, it is thus evident that the 551bp 16S rDNA sequences have potential practice value for identification of sarcophagid flies.
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