Patterns in Forensic Decapitations: A Review of the Literature and Case Report.

Separation of the head from the body can occur for a variety of reasons and in various locations across the neck. This study presents a review of the literature to identify the patterns of decapitations in forensic cases in relation to manner of death, age, and anatomical location (n = 88). The most common manner of death was suicide, followed by homicide and then accident. Ages ranged from 32 weeks prenatal to 85 years. Decapitation is reported at higher rates for individuals between 19 and 65. The majority of decapitations occurred at the midneck (second to fifth cervical vertebrae), followed by the upper neck and then the lower neck. This pattern holds true for all manners of death; however, in homicides, the percentage occurring at the midneck decreases. The findings of this study indicate some patterns in terms of manner of death, age, and location of decapitation, which could aid the medicolegal community in interpreting neck trauma. A case study is also briefly presented to illustrate findings.

Utilization of qPCR to Determine Duration and Environmental Drivers Contributing to the Persistence of Human DNA in Soil.

Little is known about the underlying mechanisms that contribute to the persistence and degradation of DNA within soil. The goals of this study are to determine the duration of mitochondrial DNA (mtDNA) and nuclear DNA (nuDNA) persistence in soils enriched by surface-level human decomposition and to better understand the contribution of environmental factors. The surface-level decomposition of three human cadavers was documented over 11 weeks. Based on quantitative PCR results, we found nuDNA to persist in soils six weeks post-placement, while mtDNA was recoverable for the entire 11-week decomposition period. Principle components analyses and Spearman's rank correlations revealed that (1) time, (2) total body score, and (3) weekly average air temperature were significantly correlated with concentrations of nuDNA and mtDNA in soil, suggesting these factors play a role in the degradation of DNA in soils.