Taking Care of the Evidence in the Forensic Genetics Laboratory

Among the most relevant applications of Human Forensic Genetics we can name the biological investigation of filiation relationships, the study of biological remains of criminal interest, the resolution of identification problems and the generation of genetic databases. Currently, analysis of genetic variations between individuals is carried out through the study of STR (short tandem repeat) molecular markers and the amplification protocols have been optimized over the years, requiring less and less amount of initial DNA to be able to obtain a profile. This has allowed an increase in the number of cases resolved with Forensic Genetics techniques, however it has also brought about a greater probability of observing alleles from contamination in the profiles. Contamination, defined as the introduction of DNA into a sample after a responsible officer takes control of the scene, must be reduced to a minimum at the scene, during sample collection, subsequently in the laboratory and with the consumables used. Within the Forensic Genetics laboratory, the division of areas is recommended, first of all, delimiting physically the pre-amplification processes from the post-amplification processes. In second place, the processing of reference samples must be separated temporally and, if possible, spatially from the casework simples in order to avoid cross-contamination of simples. The control of reagents and consumables must be carried out periodically, and all technical processes must be done with great care to avoid transfer of biological material between samples. All actors linked to the protection, collection and analysis of forensic samples must take extreme care to ensure the integrity of the sample throughout the process. In Misiones constant training is done by the professionals that work in Forensic Genetics, who also give anual lectures to a variety of professionals who participate in evidence collection. Entre las aplicaciones más relevantes de la Genética Forense Humana se encuentran la investigación biológica de relaciones de filiación, el estudio de vestigios biológicos de interés criminal, la resolución de problemas de identificación y la generación de bases de datos genéticos. Actualmente el análisis de las variaciones genéticas entre individuos se realiza a través del estudio de marcadores moleculares de tipo STR (short tándem repeat) y los protocolos de amplificación se han optimizado a lo largo de los años requiriendo de cada vez menos cantidad de ADN