Article
Latent Blood Detection and STR Analysis of Samples Collected from an American Civil War Field Hospital
Kristin N. Jones, Department of Forensic Sciences, Virginia Commonwealth University, Richmond, VA
J. Thomas McClintock, Department of Biology and Chemistry, Liberty University, Lynchburg, VA
Journal of Forensic Identification (2018) 68 (4), 509-523
Abstract
DNA analysis has recently been used to investigate samples of historical significance. During the last battle of the American Civil War (Sailor’s Creek Battlefield, Rice, VA), the Hillsman House served as a field hospital for wounded soldiers, treating more than 500 Union and Confederate soldiers. The presumed “bloodstains” on the floor under the single surgical table and two post-surgical beds provide evidence of the vast number of soldiers treated. These presumed bloodstains were collected and analyzed using various presumptive blood tests (luminol, phenolphthalein, leucomalachite green, and Rapid Stain Identification of Human Blood). To examine the genomic profiles, DNA was isolated from the collected samples, quantitated, amplified, and subjected to capillary electrophoresis. The generation of partial and complete DNA profiles confirmed the presence of human DNA, as well as the ability of DNA profiling to confirm historical accounts of soldiers being treated in a field hospital from a battle fought more than 150 years ago.
Article
Changes in the Microbiome at the Onset and End of Decomposition
Michael J. Erquiaga, Bode Technology Group, Lorton, VA
Mia R. Fabbri, Department of Chemical and Physical Sciences, Cedar Crest College, Allentown, PA
Michelle F. Kowalczyk, Criminal Identification Unit, Raleigh/Wake City-County Bureau of Identification, Raleigh, NC
Jessica E. Thornton, Alyssa J. Forrest, Erika L. Peck, and J. Thomas McClintock, Department of Biology and Chemistry, Liberty University, Lynchburg, VA
Brianna M. Cunningham, Rowan University School of Osteopathic Medicine, Stratford, NJ
Journal of Biotechnology and Bioinformatics Research (2020) 2 (4), 1-5
Abstract
Decomposition is a rapidly evolving process that is dependent on various environmental factors such as climate, temperature, insect activity, large vertebrate scavenging, and microbial activity. Although other factors such as body weight and time have been evaluated microbial activity should be considered as another major component in the decomposition process. This study was designed to investigate the microbiome and potential bacterial succession, using two different DNA extraction methods, classic microbiologic techniques and 16S ribosomal sequencing, at the onset and end of decomposition. Differences were observed between the bacterial phyla found on Day 1 versus Day 6. In the various phyla, several different bacterial species were observed such as Kurthia gibsonii, K. sibirica, Staphylococcus sciuri, S. lentus, and Serratia marcescens. An interesting change in the phyla present was observed for Day 6. None of the bacterial samples collected on any of the anatomical sites were identified in the phylum Firmicutes. In fact, most of the bacteria collected from the mouth, nose, and genitals were identified in the phyla Actinobacteria and Proteobacteria. Two different bacterial species, Myroides odoratus and Leucobacter aridicollis were present in the two phyla at Day 6 that were not observed at the onset of decomposition. Likewise, many of the bacterial species present at Day 1 were not observed in Day 6. The difference in bacterial diversity observed at the onset and end of decomposition suggest that a timeline or bacterial succession could be developed that could support post-mortem interval determinations.
Article
Touch DNA and Transfer of Biological Material
J. Thomas McClintock, Department of Biology and Chemistry, Liberty University and DNA Diagnostics, Inc., Lynchburg, VA.
ACADEMIA Letters (2021). Article 2620. https://doi.org/10.20935/AL2620.
Abstract
The human body is constantly shedding dead skin cells with an estimation between 30,000 and 40,000 skin cells that are shed every hour. Consequently, over a 24-hour period, an individual may lose almost a million skin cells. Such shed epithelial cells may have nuclei (containing 23 pair of chromosomes targeted for DNA testing) that are visible in the cytoplasm or may have lost the cellular contents due to leakage or apoptosis (programmed cell death). In addition, several studies have demonstrated the presence cell-free DNA from senescing cells which can be used for DNA proling (Botezatu et al., 2000, Garcia-Olmo et al., 2004, Anker et al., 2001, and Oleiwi et al., 2015). The nucleated cells, however, will contain DNA that can be useful for typing and linking an individual to a crime scene. In addition to the “normal” shedding process, the transfer of biological material from one object to another is influenced by both environmental (e.g., friction and pressure, and length of handling time) and genetic(e.g., “shedder” status) factors. These factors play a significant role in establishing the type and number of cells deposited on a surface of an animate or inanimate object……(Read more…Open Access Publication)
Article
Raman Spectroscopy and STR Analysis of the Elongated Skulls from the Paracas Mummies of Peru
Jessica E. Thornton, Department of Biology and Chemistry, Liberty University and DNA Diagnostics, Inc., Lynchburg, VA.
Brittany N. Johnson, Department of Biology and Chemistry, Liberty University and DNA Diagnostics, Inc., Lynchburg, VA.
Bethany R. Smith, Department of Biology and Chemistry, Liberty University, Lynchburg, VA.
Kristin N. Jones, Virginia Department of Forensic Science, Richmond, VA.
Kevin M. Richards, Virginia State Police, Counter Terrorism WMD and HazMat Unit, Lynchburg, VA.
J. Thomas McClintock, Department of Biology and Chemistry, Liberty University, Lynchburg, VA.
Journal of Biotechnology and Bioinformatics Research (2022) 4 (4), 1-8.
Abstract
Between 1880-1947, several hundred mummified bodies were excavated from burial sites in the Paracas peninsula of Peru. Each set of recovered remains displayed reduced stature and severe cranial elongation, which led many anthropologists and archaeologists to question the genetic origins of what would be colloquially referred to as the “Cone Head mummies.” Since the discovery of these bodies, suggestions have been made that the mummies’ cranial deformations point to another human species, an unknown hominid species, or even within some groups, an alien. This project sought to employ commonly used forensic techniques, including but not limited to Raman spectroscopy and DNA fingerprinting, to investigate the hair structure and genetic profile from tissue and hair samples derived from the Paracas skulls. Tissue and hair samples were subjected to comparative hair analysis, Raman spectroscopy, and DNA typing using short tandem repeat (STR) analysis. Comparative microscopic hair analysis and Raman spectroscopy of samples collected from the Paracas skull as well as from humans of varying ethnicities revealed very similar hair structures and characteristics that are associated with human hairs. Following DNA extraction and amplification of tissue samples, STR typing results demonstrated allelic profiles similar and consistent with those DNA profiles observed in modern human populations. Moreover, no foreign DNA or unusual patterns/profiles were observed in any of the samples tested. Data generated to this point strongly suggest that the Paracas mummies are of the same species as humans and not from an unknown hominid or alien society.
Article
Using Conventional STR Technology in Analyzing Biological Transfer Evidence
J. Thomas McClintock, Department of Biology and Chemistry, Liberty University, Lynchburg, VA.
In Next Generation Sequencing (NGS) Technology in DNA Analysis. H. Dash, K. Elkins, and N. Al-Snan (eds.). (2024) pp. 21-34. Academic Press. Elsevier Publishing Company, Amsterdam, Netherlands. https://doi.org/10.1016/B978-0-323-99144-5.00016-0.
Homecoming seemed to come early this year. The leaves had given way to the vibrant red and yellow fall colors; pep rallies were being held on campus; tailgating parties were popping up everywhere near the stadium; and an overall excitement seemed to fill the air on campus. After the game, there would be, no doubt, endless fraternity and sorority parties to celebrate the hometown football team’s victory. Alpha Epsilon Pi, a major fraternity on campus, was hosting a party after the game, and everyone was expected to attend. Slightly past midnight, a female at the party, who was known around campus for her sexual promiscuity, started to solicit male companions presumably for sexual favors. After a short stint with one of the fraternity brothers, the female returned to the party and continued to consume alcohol. Several drinks later, she met another male and proceeded to return to the bedroom where she had been previously with the first male companion. However, by this time the female was quite inebriated, and after a short bit of “tossing” in the bed with the second male companion she passed out. Upon awakening in the early morning, the female noticed that her underwear was moist, that her clothing was disheveled, and that almost everyone, including the two males, had left the party. Not being able to recall what had happened with the two males the night before, and after some deliberations, the female was presented to the local hospital by midmorning and claimed that she had been raped. The sexual assault nurse examiner (SANE) questioned the young lady and collected evidentiary samples such as clothing (i.e., blouse, skirt, and underwear) and swabs from various areas of her body. The evidentiary samples, as well as a known reference sample, were sent to the state forensic laboratory for DNA analysis. Known reference samples were later collected from both of the male companions and also sent to the laboratory for DNA analysis. Following the completion of the DNA testing, the state forensic laboratory reported its findings to the state’s attorney assigned to the case. In essence, the state laboratory reported that both males were minor contributors to the DNA profiles developed from the vaginal swabs of the victim, but a third major DNA profile was isolated from the underwear that was from an unidentified male. Upon further investigation and after additional testing, this DNA profile was determined to be from the fraternity brother whose bed and room were used by the female and two male companions on the night of the party. This third male was ultimately arrested and charged with first-degree rape.
The above case scenario is not an atypical situation or sexual assault charge. In this instance, the victim of such a sexual assault doesn’t recall most of the events that occurred the night before except that there was more than one male involved who probably had consensual sex with her or by force. However, in this case, the male that was ultimately arrested and charged with rape was not involved in the sexual assault, but his DNA incriminated him simply because it had transferred from his bed to the victim’s underwear. In this situation, all victim(s) should report such assaults to local authorities in an effort to identify the perpetrator(s) and find justice. This chapter will explore how such events/scenarios can occur and how forensic analysts need to be aware of such situations when the deposition of DNA is in question, especially in light of the sensitivity of today’s technology and instrumentation and the ability to detect DNA from multiple sources.