Life after death exists -- sort of. A new study finds that some genes become more active after death, according to the BBC. This is important as these genes may be able to help forensic scientists determine a Time Of Death. The study says that these genes can function for up to 48 hours after death. This isn't the first study to determine that genes can function after death. According to ValueWalk, there was a 2016 study that found gene activity in animals after death. However, this study dealt with humans.
Genes after death
Like life, death involves numerous biological processes at different times.
Body temperature drops, discoloration starts to happen and numerous other changes occur. Genes are no different, rapidly changing their expression over short post-mortem intervals. For example, a set of genes that tended to promote the growth of cancer reactivated. However, not all genes continued their expression after death. Some sets of genes, such as the ones found in muscle tissue, stopped almost immediately after death.
To understand genes, scientists look at what's called an RNA transcript, a molecule that is created when genes are switched on. Most of these molecules become the blueprints for protein creation, but some of them directly control processes in the cell. Scientists analyze the RNA transcripts to find out what is going on in the cell.
This type of analysis is called transcriptomics.
For this particular study, scientists looked at 36 different types tissue from about 540 donors, all at various stages of death. They looked for significant levels of gene activity, and whether it was dropping or rising. The scientists were trying to find out if transcriptomics was affected by a decay in gene activity after death.
Their study establishes a baseline against which future transcriptomics can be checked.
So, why are some genes still continuing their expression? The scientists believe it's because of the lack of oxygen. However, scientists aren't sure why and need to do further studies.
Forensic uses
This new study could pave the way to future forensic tests, which would allow scientists to predict a person's time of death more accurately.
Currently, scientists rely on signs such as skin discoloration and rigor mortis, the stiffening of joints and muscles that occurs after death. However, these signs aren't very precise as rigor mortis occurs hours after a person has died.
Gene activity may be more accurately able to predict the time of death within the first 24 hours as the study found that the majority of gene changes occurred 7 to 14 hours after death. Currently, that possibility is still in the future as further studies have to be done before such methods could actually be used.
