Genetics: Gene expression patterns may help determine time of death

Changes in gene expression in different tissues triggered by death can be used to predict the time of death of an individual, reports a paper published in Nature Communications this week. The study suggests that by analysing a few readily available tissues (for example, lung or skin tissue), the post-mortem interval (time elapsed since death) can be accurately determined and may have implications for forensic analyses.

To understand the tissue-specific changes to gene expression following the death of a person, Roderic Guigo and his colleagues studied RNA-sequencing data of 36 different tissues from the GTEx project, a biorepository that collects human post-mortem tissue samples. They show that the time since death has an effect on gene expression and that this effect varies from tissue to tissue. The authors develop a model to predict the post-mortem interval based on these tissue-specific gene expression changes, which could complement methods currently employed.

The authors further optimize the model to make it applicable to a forensics scenario, in which only a few tissues are likely to be available, and devise a protocol for the potential implementation in forensic pathology.