This study assessed the ability of targeted transcriptome analysis, using RNA sequencing, to reveal global changes in postmortem gene expression in liver tissues from 27 Italian and United States corpses that were 3.5-hour-old to 37-day-old.
Thanatotranscriptome studies involve the examination of mRNA transcript abundance and gene expression patterns in the internal organs of deceased humans. Postmortem gene expression is indicative of the cellular status of a corpse at the time of death, a portion of which may represent a cascade of molecular events occasioned by death. Specific gene biomarkers identify perceptible transcriptional changes induced by stochastic responses to the cessation of biological functions. Transcriptome analyses of postmortem mRNA from a tissue fragment may determine unique molecular identifiers for specific organs and demonstrate unique patterns of gene expression that can provide essential contextual anatomical information. The current study found that the single blind study that used eight liver tissue-specific gene biomarkers (e.g. AMBP and AHSG) is highly specific, with autopsy-derived organ samples correctly identified as tissues originating from postmortem livers. The results demonstrated that 98-100 percent of sequencing reads were mapped to these liver biomarkers. These findings indicate that gene expression signatures of mRNA exposed up to 37 days of autolysis can be used to validate the putative identity of tissue fragments. (publisher abstract modified)