Departamento de Criminalística da Polícia Civil do Estado do Espírito Santo, CEP: 29.045-402, Vitóri, ES, Brazil; Instituto Federal de Educação, Ciência e Tecnologia do Espírito Santo (IFES), CEP: 29.135-000, Viana, ES, Brazil.
Museu Nacional, Universidade Federal do Rio de Janeiro (UFRJ), Depto de Entomologia, CEP: 20940-040, RJ, Brazil.
Forensic Sci Int. 2020 May;310:110239. doi: 10.1016/j.forsciint.2020.110239. Epub 2020 Mar 10.
The number of sexual crimes in Brazil, as in several other countries, is very high. In many of these crimes the women raped are murdered and their bodies are found days later, in an advanced state of decomposition, with intense cadaverous fauna. Forensic Entomology studies insects and other arthropods that can be used in the expert analysis of various types of crimes. Diptera, the order of insects that comprises the two-winged or true flies, represents one of the largest known groups of insects and is the principal source of cadaveric entomofauna. Members of its Calliphoridae family are observed in cadavers in all phases of decomposition. The retrieval and identification of human Y-STR DNA from the gastrointestinal tract of Calliphoridae species Chrysomya albiceps maggots and pupae can provide a good tool for the gathering of evidence in sexual crime investigations involving rape and death, in which the abandoned victim's body is found in a putrefied state. In this study, the animal model used was a female pig, Sus scrofa, which was sacrificed in a forested area with three shots from a 0.40 calibre Taurus pistol, and inoculated with semen to its anal and vaginal regions, simulating rape and homicide. During decomposition, 20-80 maggots were collected every 24 h and preserved in 70 % alcohol, totalling 289 maggots and 157 pupae (446 immatures) over a period of 14 days (336 h) of decomposition. Each maggot was then dissected for removal of the digestive tract, which was placed in extraction buffer. The molecular phase proceeded with extraction, quantification, amplification and capillary electrophoresis of samples, testing 16 STR loci of the Y chromosome. It was possible to establish a partial Y-STR DNA profile, with the amplification of up to eight sites, by considering a combination of the samples taken at hours 144 h, 168 h, 192 h, 216 h, 240 h, 288 h, 312 h and 336 h.
巴西的性犯罪数量和其他一些国家一样非常高。在许多此类犯罪中，被强奸的女性被谋杀，几天后她们的尸体被发现，处于高度腐烂状态，有强烈的尸腐动物群。法医昆虫学研究昆虫和其他节肢动物，这些昆虫和节肢动物可用于对各种类型的犯罪进行专家分析。双翅目昆虫是由双翼或真蝇组成的昆虫目，代表着已知最大的昆虫群体之一，是尸腐动物群的主要来源。其丽蝇科的成员在所有分解阶段的尸体中都有观察到。从丽蝇科物种黄粉蝇幼虫和蛹的胃肠道中提取和鉴定人类 Y-STR DNA，可为涉及强奸和死亡的性犯罪调查中的证据收集提供良好的工具，在这些调查中，被遗弃的受害者的尸体处于腐烂状态。在这项研究中，使用的动物模型是一头母猪，Sus scrofa，它在一片森林中被一支 0.40 口径的 Taurus 手枪射击三枪后被牺牲，并向其肛门和阴道区域接种精液，模拟强奸和杀人。在分解过程中，每 24 小时收集 20-80 只幼虫，并保存在 70%的酒精中，在 14 天（336 小时）的分解过程中总共收集了 289 只幼虫和 157 只蛹（446 只幼虫）。然后，每个幼虫被解剖取出消化道，将其置于提取缓冲液中。分子阶段进行了提取、定量、扩增和样本毛细管电泳测试，测试了 Y 染色体上的 16 个 STR 基因座。通过考虑在 144 小时、168 小时、192 小时、216 小时、240 小时、288 小时、312 小时和 336 小时采集的样本的组合，可以建立一个部分 Y-STR DNA 图谱，扩增多达八个位点。
