mtDNA中COⅠ分子标记在常见食尸性蝇类鉴定中的应用

死后不同时间，在尸体上出现不同种类食尸性蝇类的演替规律，可用于准确推断死亡时间。传统上仅依据蝇类形态学特征来判断种属，但由于蝇类的形态结构复杂和种间形态差异微小等特点，对蝇类尤其是对蝇类幼虫的种属鉴别很难。因此应用分子生物学方法对食尸性蝇类及其幼虫进行种属鉴定非常重要。本研究主要是利用此方法对我国西部部分地区常见双翅目食尸性蝇类包括：开普黑蝇、大头金蝇、丝光绿蝇及部分卵，铜绿蝇、棕尾别麻蝇及部分幼虫和蛹的线粒体DNA(mtDNA)上细胞色素氧化酶辅酶Ⅰ(COⅠ)中278 bp的基因序列进行鉴别。除个别蝇类如丝光绿蝇与铜绿蝇外，该方法均能有效地将上述食尸性蝇类鉴定到种属水平。在我国，它将成为法医鉴别食尸性蝇类种属的可靠依据。

The availability of mitochondrial DNA cytochrome oxidaseI gene for the distinction of forensically important flies in China

Sarcosaphagous flies are frequently found on dead bodies shortly after death. Species within this family differ in their developmental times, so an accurate identification of every species is necessary for the correct estimation of the post mortem interval (PMI). Identification of specimens is traditionally performed using their morphological features. The morphological similarity of sarcosaphagous flies especially their eggs, larva and pupae, poses a challenge for forensic entomologists. Therefore a molecular method was established for species identification. In this study, A 278 base pair region of mitochondrial DNA (mtDNA) coding for cytochrome oxidase subunit one (CO Ⅰ ) was investigated for identification of the following forensically important species of sarcosaphagous flies from western China, including Ophyra capensis (Wiedemann), Chrysomya megacephala ( Fabricius), Lucilia sericata ( Meigen), Lucilia cuprina ( Wiedemann), and Boettcherisca peregrina ( Robineau-Desvoidy). The results indicated that the CO Ⅰ region sequenced allowed identification of major species, providing separation of congeneric species with high support. In contrast, the data could not distinguish taxa from the same species group, i. e. the L. sericata and L. cuprina groups because of low sequence divergence.