Evaluation of antisera for bloodstain grouping. I. ABH, MN, and Rh

Sixty-eight different commercially available blood grouping antisera and lectins with ABH, MN, and Rh D, C, E, c, and e specificities were serologically evaluated for their applicability to bloodstain antigen determination. The characteristics of the antisera were determined with red cells, with fresh bloodstains, and with series of aging bloodstains. The Rh antisera were tested under a variety of serological conditions and with bloodstains on various substrata. Additionally, studies on optimization of absorption-elution procedure variables were carried out, and some data on the storage characteristics of red cells and blood grouping antisera were gathered.     

DNA analysis of ingested tomato and pepper seeds

Ingested food is one of the important types of forensic evidence obtained during a medicolegal autopsy. Many materials containing seeds pass through the human digestive system and are still recognizable; thus, they can be valuable for providing investigative leads. Currently, the identification of seeds relies on microscopic and morphologic examination. However this method sometimes can be problematic. For example, the microscopic appearance of the ingested tomato and pepper seeds is very similar; thus, it is not always easy to distinguish these seeds by comparing their physical characteristics. Tomato and pepper seeds were selected as a model system to assess the value of performing DNA analysis as an alternate and/or complimentary means of seed identification. Results of blind testing indicate that the deoxyribonucleic acid-amplified fragment length polymorphism (DNA-AFLP) results were able to discriminate between pepper and tomato seed samples after they passed through the digestive system.     

Empirical Limits for the Forensic Assessment of PTSD Litigants

This paper discusses the limits of expert opinion on posttraumatic stress disorder (PTSD) in personal injury claims. The construct of PTSD is hampered by several empirical limitations. Multiple reliable measures of PTSD exist, but have not been evaluated sufficiently within litigating samples and are infrequently used by forensic assessors. Common methods for trauma screening appear insensitive. Opinions about causation of PTSD and disability are complicated by retrospective memory biases, as well as the failure of most anxiety disorders to be detected within primary medical care. PTSD appears to have a steep spontaneous remission curve during the first year, but at least 10% of trauma-exposed people suffer chronic distress. Little is known about the course beyond 1 year. Efficacious psychological treatments have been developed for PTSD, but are not in common use limiting claimants access to rehabilitative treatments. Research on functional disability associated with PTSD is in its infancy, but it seems likely that PTSD will account for only a part of the variance in work disability. We provide suggestions for improving forensic practice, advising the courts about the limitations of forensic opinions, and necessary research.     

Selection of twenty-four highly informative SNP markers for human identification and paternity analysis in Koreans

A number of DNA marker types suitable for human identification and parentage testing have been developed, of which single nucleotide polymorphisms (SNPs) merit attention as they are abundant, genetically stable, and amenable to high-throughput automated analysis. In this regard, 24 highly informative SNP markers representing each 22 autosome and both sex chromosomes were selected, and the allele and genotype frequencies of these SNPs were determined in a group composed of 30 unrelated Koreans. Based on frequency data from this group, the estimated probability of identity (P(I)) and probability of paternity exclusion (P(E)) with 22 autosomal SNP loci were 1.905x10(-10) and 98.9%, respectively. The SNPs in this study offer a small but highly accurate database that will be an essential reference for SNP-based forensic application in the future.     

The study of metabolite-to-parent drug ratios of methamphetamine and methylenedioxymethamphetamine in hair

The metabolite-to-parent drug ratios were determined in the hair of 2444 methamphetamine (MA) abusers who had produced MA-positive hair results from 2001 to May 2005 and in the hair of 53 ecstasy abusers who had produced positive methylenedioxymethamphetamine (MDMA) hair results from 2002 to May 2005. For the hair analyses, hair strands were washed, cut into small pieces and extracted for 20 h in 1 mL methanol containing 1% HCl. Drugs in the extract were determined by gas chromatography-mass spectrometry (GC-MS) using selective ion monitoring after derivatization with trifluoroacetic anhydride. The six range groups were divided as follows on the basis of MA concentrations in hair (n = 2389): 0.5-5 ng/mg (n = 950), 5-10 ng/mg (n = 582), 10-20 ng/mg (n = 503), 20-30 ng/mg (n = 160), 30-40 ng/mg (n = 80), more than 40 ng/mg (n = 114) to assess the correlations between MA concentrations and metabolite-to-parent drug ratios. In groups of higher MA concentrations, lower ratios of AP/MA were found, and there was a statistically significant difference among six range groups. Comparisons of age groups (tens, twenties, thirties, forties, fifties, and sixties) and male and female subjects for the ratios of AP/MA showed a statistically significant difference. The detection of metabolites and the parent drug with reasonable ratios was found to be a useful indicator for distinguishing internal drug incorporation from external contamination. In our study, MA users can produce 0.4-116% (mean = 9%) of amphetamine (AP) concentrations in hair, and ecstasy users 1-110% (mean = 12%) of methylenedioxyamphetamine (MDA) in appropriately washed hair samples.