Potencial de Elucidação de Crimes Sexuais sem Suspeito por Meio do Uso de Bancos de Perfis Genéticos

Abstract

The sexual crimes rate is high in Brazil and consequently there is an accumulation of stored evidences without being analyzed with DNA tests. These evidences are not processed for several reasons, like the fact that the investigation, in most cases, does not indicate a suspect to confront. However, with the advent of DNA databases, these evidences have being seen as valuable sources of information for the investigations. International studies haved already related the success of the large-scale processing of these evidences to evaluate the rate of obtaining coincidences and of identifying serial aggressions using DNA databases. In Brazil, due to the recent implantation of DNA databases, studies are needed to assess their power of criminal elucidation. Thus, the objective of this study was to evaluate the potential of the DNA Databases Goias State (Brazil) (BPG-SPTC/GO) in the elucidation of sex crimes without suspect through the insertion of genetic profiles obtained from evidences of sex crimes without suspect occurred in Goiás from 2004 to 2018. The samples were submitted to DNA extraction by differential lysis, followed by the amplification of STR autosomal markers, capillary electrophoresis analysis in the ABI 3500 genetic analyzer, and insertion in the BPG-SPTC/GO using the CODIS 7 software. We evaluated the rates of samples with eligible for insertion profiles, of coincidence and of serial aggression identification; and for the statistical approaches the programs Epi Info ™ v.7 and BioEstat 5.0 were used. A total of 275 samples were analyzed, of which 202 had eligible genetic profiles for insertion (73,45%). Of this total, 176 were inserted, generating 60 hits, and 32 criminal investigations were aided, all related to sexual assaults in series and to stranger perpetrators. The use of DNA databases proved to be an excellent tool for elucidating sex crimes without suspect. Moreover, their use associated with a large-scale analysis of evidences with presence of spermatozoa showed to be able to generate greater speed of elucidation without the loss of the elucidative potential with the passage of time. In addition, the results indicated greater elucidation of sexual offenses of unknown perpetrators and the need to increase the number of genetic profiles in DNA Databases.