DNA Barcoding in Forensic Vertebrate Species Identification

Abstract

Animal identification is essential in a large number of forensic cases, including bush meat harvest, unregulated trade in protected species or species' derivatives, introduction of exotic species without a proper permit and food fraud. The analysis of morphological traits has been the most traditional method used for species identification and taxonomy. However, when morphological identification is compromised, genetic identification can be used to associate sequences from unknown samples to a sequence from a reference sample. Based on a standard region of 650 base pairs of the subunit I of cytochrome c oxidase mitochondrial gene (COI) and using a validated reference database, the DNA Barcoding system for cataloging and identifying animal species has been proposed. In order to test the utility of DNA Barcoding in forensic vertebrate species identification, COI sequences from previously identified samples from human and a variety of domestic and wild specimens of Brazilian mammals, birds, fishes were compared against the Barcode of Life Database (BOLD). BOLD provided a correct species-level identification for 12 out of the 20 queried sequences (60%) and presented the correct species as the best matched one for 17 out of 18 samples morphologically identified to this level (94%). Cases where BOLD did not deliver a species level identification were associated with the controversial taxonomic status of some species, the possible occurrence of a biological event like hybridization and the lack of representation of some groups in the database. The results showed that DNA Barcoding is already effective for species identification in many cases and, although presenting some limitations, the use of the tool must be improved and widespread in forensic casework.

Investigação De Colisões Entre Aves E Aeronaves No Brasil Com O Uso Do Dna Barcoding

“…Fragmentos de aproximadamente 650 pb da região 5' do gene COI foram amplificados com a utilização dos iniciadores FishF1/FishR1 (WARD et al, 2005) e LCO1490/HCO2198 (FOLMER et al, 1994). As condições de PCR e sequenciamento foram as mesmas descritas por Carvalho (2014), com a diferença de que parte das sequências foi obtida em um analisador genético ABI 3500 REA -Revista de estudos ambientais (Online) v.21, n. 2, p.71-79, jul./dez. 2019 (Applied Biosystems).…”

“…2019 (Applied Biosystems). Da mesma forma, além daqueles descritos por Carvalho (2014) foram utilizados também os programas SeqScape 3 (LIFE TECHNOLOGIES CORPORATION, 2012), para a montagem e avaliação da qualidade das sequências, e MEGA 6 (TAMURA et al, 2013), para os alinhamentos e tradução, permitindo identificar a ocorrência de heteroplasmia ou de códons de parada estranhos. As sequências consensuais obtidas foram confrontadas com aquelas depositadas no banco de dados Species Level Barcode Records da plataforma BOLD com o uso de sua própria ferramenta de busca.…”

Panorama atual da Genética Forense no Brasil: aspectos tecnológicos, legais e estratégicos

“…Além da aplicação na identificação humana, existem muitas outras áreas de emprego da genética forense, tais como a identificação de espécies vegetais [8,9] e identificação de espécies animais [10][11][12][13][14], dentre tantas outras aplicações possíveis.…”

Characteristic of CO1 gene in "Bonita", one of the female tiger Panthera tigris sumatrae in East Sumatra

“…One of the characters observed can be in the form of molecular aspects. The latest DNA-based identification method is developed for animal forensic investigation [8,9] and known as DNA barcoding technology, which was established in 2003 [10,11]. Currently, DNA barcoding has been used as a standard protocol for the rapid identification of animals and plants at the species level.…”