Detection of medical examiner cases from review of cremation requests

Title 9, Chapter 19, Article 3 of the Arizona Administrative Code requires all bodies that are to be cremated must have the death certificate reviewed by a county medical examiner. In Tucson, AZ, and surrounding Pima County, all cremation requests are submitted to the Forensic Science Center, where the death certificates are reviewed by one of 5 board-certified forensic pathologists. In 2002, there were 5557 cremation requests, and in 2003 there were 5662 cremation requests. Of these requests, 670 (12.1%) and 447 (7.9%) death certificates were flagged for further investigation in 2002 and 2003, respectively. Eventually, 47 cases (0.8% of total, 7.0% of flagged cases) were accepted as medical examiner cases in 2002, and 43 cases (0.8% of total, 9.6% of flagged cases) were accepted as medical examiner cases in 2003. In 2002, the majority of cases were handled as a records review; however, 4 cases were brought in for autopsy and 1 was certified after an external examination only. In 2003, all cases were certified via a records review. The manner of death in all but 3 of these deaths was certified as accident, with complications of remote trauma being the most common proximate cause of death. The 3 most common injuries were complications of fractured pelvis or femur (15 in 2002, 22 in 2003), head injury due to fall (18 in 2002, 8 in 2003), and complications of remote motor vehicle accident (3 in 2002, 6 in 2003). The other 3 deaths included 2 homicides, 1 in each year, and 1 suicide in 2003.     

Forensic mitochondrial DNA analysis of 691 casework hairs

A five year retrospective review of mitochondrial DNA (mtDNA) analysis on 691 casework hairs was carried out. A full or partial mtDNA profile was obtained for > 92% of hairs. With increasing age of the hair, the likelihood of obtaining a full profile decreased, although "mini-primer sets" could often be used to capture a partial profile. With increasing color and diameter of the hair, the likelihood of obtaining a profile increased. Full or partial profiles were obtained on more than 80% of 114 hairs < or = 1.0 cm. Mixtures were observed in 8.7% of hairs tested; mixtures increased with the age of the hair and were presumed to be due to exterior surface contamination that could not be sufficiently cleaned prior to extraction, since the overall level of laboratory contamination was low. The frequency of sequence heteroplasmy was 11.4%, and both hot-spot and novel sites were observed. In about one-third of these observations, another sample in the case showed either the same heteroplasmic site or a nucleotide substitution at that site.