Analysis of RNA stability in forensic specimens

Ribonucleic acid (RNA) analysis presents a unique, novel opportunity to answer a wide range of questions in forensic science. The dynamicity of the transcriptome has led to it being suggested as a novel source of diagnostic information in forensic pathology. However, RNA is exceptionally labile. This research has characterised the post-mortem degradation behaviour of tissue RNA in an animal model, the laboratory mouse; with the aim of identifying a post-mortem interval during which gene expression analysis provides informative and reliable results. It was extremely encouraging that over the three day post-mortem interval examined, the yield of RNA from skeletal muscle, kidney, liver and heart tissue did not fall to such a level that it became unanalysable. Interestingly, individual RNAs were found to exhibit unique decay behaviour during the post-mortem interval; some significantly more stable than others. In the tissues of mice decomposed at room temperature, RNAs remained stable for at least the first 12 hours post-mortem; after which the observed differential decay skewed their expression profiles. This poses an interpretational obstacle for gene expression data where an extended time lag exists between death and sampling, and highlights the requirement for future work to consider novel data normalisation strategies. Overall, it is suggested that using RNA degradation as an indicator of post-mortem interval is fraught with difficulties: such as its dependence on the environmental conditions (specifically ambient temperature), differential RNA decay behaviour between tissue types and storage media, and inherently strong variability between replicates.

Name dc:type.qualificationname

phd

Level dc:type.qualificationlevel

doctoral-pg

Grantor dc:publisher.institution

University of Strathclyde

Year dc:date.issued

2015

Author dc:creator

• McCallum, Nicola Ann

DOI

10.48730/pccg-ws60

Identifier

T13981

OAI identifier oai:identifier

oai:strathclyde:g445cd15v