Validation of a reaction volume reduction protocol for analysis of Y chromosome haplotypes targeting DNA databases.

The use of Y chromosome haplotypes, important for the detection of sexual crimes in forensics, has gained prominence with the use of databases that incorporate these genetic profiles in their system. Here, we optimized and validated an amplification protocol for Y chromosome profile retrieval in reference samples using lesser materials than those in commercial kits. FTA® cards (Flinders Technology Associates) were used to support the oral cells of male individuals, which were amplified directly using the SwabSolution reagent (Promega). First, we optimized and validated the process to define the volume and cycling conditions. Three reference samples and nineteen 1.2 mm-diameter perforated discs were used per sample. Amplification of one or two discs (samples) with the PowerPlex® Y23 kit (Promega) was performed using 25, 26, and 27 thermal cycles. Twenty percent, 32%, and 100% reagent volumes, one disc, and 26 cycles were used for the control per sample. Thereafter, all samples (N = 270) were amplified using 27 cycles, one disc, and 32% reagents (optimized conditions). Data was analyzed using a study of equilibrium values between fluorophore colors. In the samples analyzed with 20% volume, an imbalance was observed in peak heights, both inside and in-between each dye. In samples amplified with 32% reagents, the values obtained for the intra-color and inter-color standard balance calculations for verification of the quality of the analyzed peaks were similar to those of samples amplified with 100% of the recommended volume. The quality of the profiles obtained with 32% reagents was suitable for insertion into databases.

First forensic records of termite activity on non-fossilized human bones in Brazil / Primeiros relatos forenses de atividade de térmitas em ossos humanos não fossilizados no Brasil

Abstract The aim of this study was to describe the first records of termite activity on non-fossilized human bones in Brazil. The cases reported in this study resulted from forensic analysis of six human skeletons found in northeastern Brazil between 2012 and 2014. Traces of tunnels and nests commonly produced by termites were found on several human bone surfaces as well as the specimens and characteristic signs of osteophagic activity. In four cases, the species were identified: Amitermes amifer Silvestri, 1901, Nasutitermes corniger (Motschulsky, 1855) (on two skeletons), and Microcerotermes indistinctus Mathews, 1977. In two other cases, the activity of termites on bone surfaces was evidenced by remains of nests and tunnels produced by these insects. At least in the samples of human remains available for this report, the number of termites collected was greater on bones found during autumn, the rainy season in the Northeast of Brazil. The human bones examined showed termites like insects with lots of strength at bone degradation, capable of continuing the process of decomposition of human remains even in completely skeletonized bodies.

Resumo O objetivo deste estudo foi descrever os primeiros relatos de atividade de térmitas em ossos humanos não fossilizados, no Brasil. Os casos relatados neste estudo resultaram da análise pericial de seis esqueletos humanos encontrados no Nordeste do Brasil, entre os anos de 2012 e 2014. Vestígios de túneis e ninhos comumente produzidos por cupins foram encontrados em várias superfícies dos ossos humanos, bem como a presença de espécimes e característicos sinais de atividade osteofágica. Em quatro casos, foram identificadas as espécies: Amitermes amifer Silvestri, 1901, Nasutitermes corniger (Motschulsky, 1855) – em duas ossadas, e Microcerotermes indistinctus Mathews, 1977. Em dois outros casos, a atividade de cupins sobre superfícies ósseas foi evidenciada pelos restos de ninhos e túneis produzidos por esses insetos. Pelo menos nas amostras de restos humanos disponíveis para o presente estudo, o número de térmitas recolhido foi maior em ossos encontrados durante o outono, a estação chuvosa no Nordeste do Brasil. Os ossos humanos analisados ​​apresentaram cupins como insetos com muita força na degradação óssea, com capacidade de prosseguir o processo de decomposição de restos humanos, mesmo em corpos completamente esqueletizados.

First forensic records of termite activity on non-fossilized human bones in Brazil.

The aim of this study was to describe the first records of termite activity on non-fossilized human bones in Brazil. The cases reported in this study resulted from forensic analysis of six human skeletons found in northeastern Brazil between 2012 and 2014. Traces of tunnels and nests commonly produced by termites were found on several human bone surfaces as well as the specimens and characteristic signs of osteophagic activity. In four cases, the species were identified: Amitermes amifer Silvestri, 1901, Nasutitermes corniger (Motschulsky, 1855) (on two skeletons), and Microcerotermes indistinctus Mathews, 1977. In two other cases, the activity of termites on bone surfaces was evidenced by remains of nests and tunnels produced by these insects. At least in the samples of human remains available for this report, the number of termites collected was greater on bones found during autumn, the rainy season in the Northeast of Brazil. The human bones examined showed termites like insects with lots of strength at bone degradation, capable of continuing the process of decomposition of human remains even in completely skeletonized bodies.