Intracranial impalement with entrance site in the mandibular region: postmortem elucidation of an accidental fall on a wooden plant stick.

A 78-year-old woman with a history of transient ischemic attacks was found in the doorway of her house in a somnolent and unresponsive condition. In the right mandibular region, a small skin wound was localized, which was surgically treated. Six days after admission to the hospital, an exploratory craniotomy was performed because of abnormal CT findings. Apart from tissue lesions and hemorrhages a small bone fragment was detected in the right cerebral cortex, which was removed. After 11 days in hospital, the patient died from failure of central regulatory functions. At the forensic autopsy, a 15 cm long wound track running upward from the skin wound in the right mandibular region through the bony skull base to the right parietal lobe of the brain was noted. Apparently, the surgically removed bone fragment had been displaced from the right middle cranial fossa. The site of the incident in the deceased's house was inspected again and a bamboo pole used to stabilize a potted plant standing on the floor was found and sent to the trace evidence laboratory. Analysis showed blood and tissue deposits from the victim. On the basis of all the findings and the circumstances of the case, a fatal impalement injury caused by an accidental fall could be assumed.

Recovery of latent fingerprints and DNA on human skin.

The project "Latent Fingerprints and DNA on Human Skin" was the first systematic research in Europe dealing with detection of fingerprints and DNA left by offenders on the skin of corpses. One thousand samples gave results that allow general statements on the materials and methods used. The tests were carried out according to a uniform trial structure. Fingerprints were deposited by natural donors on corpses. The latent fingerprints were treated with magnetic powder or black fingerprint powder. Afterward, they were lifted with silicone casting material (Isomark(®)) or gelatine foil. All lifts were swabbed to recover DNA. It was possible to visualize comparable and identifiable fingerprints on the skin of corpses (16%). In the same categories, magnetic powder (18.4%) yielded better results than black fingerprint powder (13.6%). The number of comparable and identifiable fingerprints decreased on the lifts (12.7%). Isomark(®) (14.9%) was the better lifting material in comparison with gelatine foil (10.1%). In one-third of the samples, DNA could be extracted from the powdered and lifted latents. Black fingerprint powder delivered the better result with a rate of 2.2% for full DNA profiles and profiles useful for exclusion in comparison with 1.8% for the magnetic powder traces. Isomark(®) (3.1%) yielded better results than gelatine foil (0.6%).

Low-volume amplification on chemically structured chips using the PowerPlex16 DNA amplification kit.

In forensic DNA analysis, improvement of DNA typing technologies has always been an issue. It has been shown that DNA amplification in low volumes is a suitable way to enhance the sensitivity and efficiency of amplification. In this study, DNA amplification was performed on a flat, chemically structured glass slide in 1-microl reaction volumes from cell line DNA contents between 1,000 and 4 pg. On-chip DNA amplification reproducibly yielded full allelic profiles from as little as 32 pg of template DNA. Applicability on the simultaneous amplification of 15 short tandem repeats and of a segment of the Amelogenin gene, which are routinely used in forensic DNA analysis, is shown. The results are compared to conventional in-tube amplification carried out in 25-microl reaction volumes.

[Possible applications of Y chromosome STRs in examination of abortion tissue]. / Anwendungsmöglichkeiten von Y-chromosomalen STRs bei der Untersuchung von Abrasionsmaterial.

By application of Y-chromosomal STRs, DNA analysis of abortion material can be considerably facilitated since great excess of maternal DNA is tolerated without disturbing the Y-STR amplification. If paternity can't be excluded on the basis of the Y-STR haplotype, further examinations must follow, e.g. autosomal STR analysis. For this purpose, histological preparation of the abortion tissue might still be necessary. Different Y-chromosomal haplotypes of embryo and putative father usually lead to an exclusion from paternity. Based on four case examples, the feasibility of this method is discussed.