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.