Identification of Exhumed Remains of Fire Tragedy Victims Using Conventional Methods and Autosomal/Y-Chromosomal Short Tandem Repeat DNA Profiling

Abstract

In a fire tragedy in Manila in December 1998, one of the worst tragic incidents which resulted in the reported death of 23 children, identity could not be established initially resulting in the burial of still unidentified bodies. Underscoring the importance of identifying each of the human remains, the bodies were exhumed 3 months after the tragedy. We describe here our work, which was the first national case handled by local laboratories wherein conventional and molecular-based techniques were successfully applied in forensic identification. The study reports analysis of DNA obtained from skeletal remains exposed to conditions of burning, burial, and exhumation. DNA typing methods using autosomal and Y-chromosomal short tandem repeat (Y-STR) markers reinforced postmortem examinations using conventional identification techniques. The strategy resulted in the identification of 18 out of the 21 human remains analyzed, overcoming challenges encountered due to the absence of established procedures for the recovery of mass disaster remains. There was incomplete antemortem information to match the postmortem data obtained from the remains of 3 female child victims. Two victims were readily identified due to the availability of antemortem tissues. In the absence of this biologic material, parentage testing was performed using reference blood samples collected from parents and relatives. Data on patrilineal lineage based on common Y-STR haplotypes augmented autosomal DNA typing, particularly in deficiency cases.

Brain banks: benefits, limitations and cautions concerning the use of post-mortem brain tissue for molecular studies

“…This property is valuable in forensic pathology and paleontology, allowing limited genetic studies in tissues maintained for thousand of years (Marotta and Rollo 2002;Konomi et al 2002;Paabo et al 2004;Calacal et al 2005;Luciani et al 2006). However, DNA is vulnerable to degradation in liquid solutions, particularly fixatives used for tissue preservation in current pathological practice.…”

Y chromosome STR typing in crime casework

“…Y-STRs in combination with autosomal STRs will thus be employed preferentially in sexual assault cases. Furthermore, the method has proved useful in reconstructing paternal relationship e.g., in mass disaster investigations [3] and Y-STRs as well as Y-SNPs can provide intelligence information on the ethnic origin of a male DNA donor [4]. The principal weakness of Y chromosome STR analysis is that even when a crime sample matches the Y-STR profile of a suspect, patrilineal relatives of the suspect cannot be excluded as being the donor of the stain.…”

A novel multiplex assay for simultaneously analysing 13 rapidly mutating Y-STRs

“…Y-STR analysis has also been considered an important tool in forensic genetics, especially in the analysis of sexual offences; paternity testing and missing person investigations [2][3][4]. The most advantageous aspect of Y-STR analysis in forensic genetics is that it can detect low level of male DNA in a high background of female DNA [5] as typically confronted within cases of sexual assault.…”