C Campobasso

Human and insect mitochondrial DNA analysis from maggots.

During the course of our forensic investigations, we have encountered situations where it would have been useful to have evidence, other than direct contact between the two, for concluding that a carrion-fly maggot developed on a particular human victim. If a maggot collected during a death investigation did not develop on the victim, then its age is not relevant to estimating the postmortem interval. In this study we demonstrate that mitochondrial DNA (mtDNA) sequence data can be obtained from the dissected gut of a maggot that had fed on human tissue. These data can be used to identify both the human corpse upon which the maggot had been feeding and the species of the maggot itself.

Determination of Postmortem Interval from Old Skeletal Remains by Image Analysis of Luminol Test Results

The luminol test is routinely used in forensic serology to locate blood traces and identify blood stains not visible to the naked eye; its sensitivity is reported as ranging from 1:100,000 to 1:5,000,000. To evaluate the possibility of correlating the postmortem interval with blood remnants in bone tissue, the luminol test was performed on 80 femurs with a known time of death, grouped in five classes. Powdered bone (30 mg) was recovered from compact tissue of the mid-shaft of each femur and was treated with 0.1 mL of Luminol solution (Sirchie Finger Print Laboratories, Inc.). The reactions were observed in a dark room and filmed by a TV camera equipped with a recording tape. An intense chemiluminescence was observed after a few seconds in all 20 femurs with a PMI ranging from 1 month to 3 years. On the 20 femurs with a PMI ranging from 10-15 years, a clear chemiluminescence was visible with the naked eye in 80% of the sample. Among the 20 femurs with a PMI ranging from 25 to 35 years, a weaker chemiluminescence appeared in 7 femurs (33% of the sample). In the 10 femurs with a PMI ranging from 50 to 60 years, a faint reaction was observed only in a single femur. In none of the ten femurs with a PMI over 80 years was chemiluminescence observed. The image of each reaction was computerized and analyzed for gray scale. The results of image analysis show a possible quantitative relationship between the PMI and luminol chemiluminescence in powdered bone.

Craniofacial Identification by Comparison of Antemortem and Postmortem Radiographs Two Case Reports Dealing With Burnt Bodies

Two cases of positive identification of burnt bodies by radiographic comparison are reported. They emphasize that antemortem radiographs of the head are an important but sometimes overlooked source of information which can frequently provide useful objective data for comparison purposes. A positive identification can easily be achieved by medical examiners through visual comparison of the antemortem with the postmortem cranial and facial structures, even of bodies severely damaged by fire. In these bodies the radiographs of the skull can graphically depict structures which are often unique to the individual, such as the frontal sinus pattern and the morphology of dental restorations. However, the process of identification through radiographs is appropriate only in burnt bodies in which antemortem radiographs of the alleged deceased are available for comparison and unique craniofacial structures are still present on the body in a well-preserved state or at least not completely destroyed by fire, depending on the extent of the burn injury. Matching of corresponding features seems preferable to other methods of personal identification such as skull-photo superimposition, morphometric analysis, and/or other computer-aided methods since these techniques need trained personnel, as well as expensive equipment which is not invariably available in the medical examiners office or department of anthropology.