Use of subpopulation data in Australian forensic DNA casework

DNA profiling evidence presented in court should be accompanied by a reliable estimate of its evidential weight. In calculating such statistics, allele frequencies from commonly employed autosomal microsatellite loci are required. These allele frequencies should be collected at a level that appropriately represents the genetic diversity that exists in the population. Typically this occurs at broadly defined bio-geographic categories, such as Caucasian or Asian. Datasets are commonly administered at the jurisdictional level. This paper focuses on Australian jurisdictions and assesses whether this current practice is appropriate for Aboriginal Australian and Caucasian populations alike. In keeping with other studies we observe negligible differences between Caucasian populations within Australia when segregated geographically. However segregation of Aboriginal Australian population data along contemporary State and Territory lines appears to mask the diversity that exists within this subpopulation. For this reason datasets collated along more traditional lines may be more appropriate, particularly to distinguish the most genetically differentiated populations residing in the north of the continent.     

Report of a fatal, acute tripelennamine intoxication.

A death resulting from tripelennamine overdose in a 19-year-old male Caucasian is reported. The patient died 7 h after ingesting approximately twenty 50-mg tripelennamine tablets. A concentration of 1.0 mg/100 ml was found in the blood. All tissue concentrations were measured by ultraviolet spectroscopy and verified by gas-liquid chromatography. Significant findings included pulmonary edema and multiple small petechial hemorrhages in the soft tissue of the scalp.     

Isolation of deoxyribonucleic acid (DNA) from saliva and forensic science samples containing saliva.

Saliva and saliva-stained materials were examined as potential sources of deoxyribonucleic acid (DNA) for DNA analysis and identity testing. In this paper, the authors demonstrate that DNA was isolated and DNA banding patterns suitable for DNA typing were obtained from fresh saliva and various saliva-stained materials, such as envelopes, buccal swabs, gags, and cigarettes. Furthermore, DNA and DNA banding patterns were obtained from actual forensic evidentiary samples containing mixed saliva/semen stains. The DNA banding patterns obtained from saliva or saliva-stained material were indistinguishable from the patterns obtained from blood or hair from the same individual. Intact DNA was readily isolated and DNA banding patterns were obtained from saliva stored at -20 degrees C and dried saliva stains stored under varying conditions. We conclude that saliva and saliva-stained material can be good sources of DNA for analysis and for DNA typing in certain forensic settings.     

Legal perceptions of forensic DNA profiling part I: a review of the legal literature

A forensic biologist is usually involved in the criminal justice system process somewhere between the police and the legal system, interacting in a practical context regularly and extensively with both. Forensic DNA research and development commonly involves initiatives that encroach into the neighbouring domains of the law enforcement or legal agencies. Despite this level of association, establishing meaningful cross-disciplinary communication and understanding within the justice system remains a challenge. As an example, there is an abundance of literature relating to forensic DNA profiling in legal and criminological periodicals. Such journals are perhaps outside the regular reading of forensic scientists and much of the legal discussion appears to go unnoticed. This situation is understandable; however, it is also undesirable particularly as forensic DNA developments are intertwined with significant changes in legislation and contentious issues of privacy, civil liberty and social justice. This paper attempts to address this shortcoming directly by summarising - from the viewpoint of a forensic scientist - some of the discussion in the legal literature. In particular the review focuses on discussion raising ideological and ethical concerns. Awareness of these views is of relevance to forensic science. It assists us to accurately place DNA evidence into context and to develop its role in achieving the broader criminal justice system objectives. Understanding the discussion also provides a way to enter the debate and communicate at an appropriate level the true potential of DNA to the legal community.