Current genetic methodologies in the identification of disaster victims and in forensic analysis

Abstract

This review presents the basic problems and currently available molecular techniques used for genetic profiling in disaster victim identification (DVI). The environmental conditions of a mass disaster often result in severe fragmentation, decomposition and intermixing of the remains of victims. In such cases, traditional identification based on the anthropological and physical characteristics of the victims is frequently inconclusive. This is the reason why DNA profiling became the gold standard for victim identification in mass-casualty incidents (MCIs) or any forensic cases where human remains are highly fragmented and/or degraded beyond recognition. The review provides general information about the sources of genetic material for DNA profiling, the genetic markers routinely used during genetic profiling (STR markers, mtDNA and single-nucleotide polymorphisms [SNP]) and the basic statistical approaches used in DNA-based disaster victim identification. Automated technological platforms that allow the simultaneous analysis of a multitude of genetic markers used in genetic identification (oligonucleotide microarray techniques and next-generation sequencing) are also presented. Forensic and population databases containing information on human variability, routinely used for statistical analyses, are discussed. The final part of this review is focused on recent developments, which offer particularly promising tools for forensic applications (mRNA analysis, transcriptome variation in individuals/populations and genetic profiling of specific cells separated from mixtures).

Forensic Genetics and Genotyping

“…For example, prolonged exposure of even a large blood stain to the environment can degrade the DNA and make it unsuitable for further analysis (7). Environmental sources of degradation are chemical (acids, bases, strong oxidizing agents), physical (heat and sunlight) and biological (bacteria and fungi) (1,3). The most common source of degradation is biological in the form of mold and mildew.…”

“…In comparison to soft tissues, hard tissues are greatly resistant to autolysis and decomposition caused by environmental factors. Therefore, bones, teeth and nails are the only source of DNA in some forensic cases (3,29). Miloš et al have shown that femur provided the best success rates while clavicle, ulna, and radius provided the lowest success rates (23).…”

“…paternity testing), corpse identification, forensic casework (criminal matters), missing person investigation and massfatality identification (e.g. terrorist attacks, airplane crash, tsunami disaster, war crimes) (2)(3)(4). Personal identification and relatedness to other individuals are the two main subjects of forensic DNA analysis (2).…”

“…eyes and hair color). The discrimination potential of these systems is low compared to DNA polymorphisms (3,5). Any two humans are 99,9% identical in their nucleotide sequences (1,2,4).…”

DNA capture-probe based separation of double-stranded polymerase chain reaction amplification products in poly(dimethylsiloxane) microfluidic channels

“…These devices combined with analysis of short tandem repeats (STRs) will improve both forensic human identification and medical diagnostics, in particular genetic alteration linked with mutation in STR regions [1][2][3] in terms of speed, cost, and accuracy of the results. Modern STR analysis systems 4,5 are based on genome DNA amplification with subsequent electrophoretic separation=detection of multiple STR loci using complex and expensive CE devices.…”