Scientists from the University of Washington discovered death surviving genes that remain active even after the physical shutdown of the organism.
Hundreds of genes were still found to be functioning despite the lack of brain activity, breathing and heart beating in the body.
The study involved zebrafish and mice. The researchers measured the presence of messenger RNA, which is used by cells to produce proteins. The monitoring took place four days after the animal’s death.
The After-Death Genetics
In the livers and brain samples taken from the small animals, the general mRNA levels would continuously decrease. What came as a surprise was the fact that the mRNA linked to 515 mouse genes and 548 zebrafish genes revealed peaks of activity. In order to function, the genes would have needed sufficient energy and activity support from cells.
While other genetic materials appeared to decay, the series of 1,036 genes seemed to be even more active in the three days following death. Moreover, in comparison with the rest of the genes in the organism, their activity was not chaotic.
The Role of Surviving Genes
The surviving genes were involved in processes like stress regulation, immunity, or inflammation. Another interesting fact is the return to activity of a gene that is usually connected with the life of the fetus, and it turns off after birth.
The positive functions revealed by the existence of these genes may indicate the organism’s effort to heal itself. However, scientists believe that the opposite scenario may be also plausible: the activity of the genes is a sign that the organism is undergoing full shutdown.
Supporting this idea is the fact that another kind of gene that became active was one commonly associated with cancer.
As many people that have liver transplants experience a type of cancer, the scientists believe that the activity of these genes is responsible for risks to the health of humans that receive the transplants.
Researchers point out that people who receive transplants have to take special medication that suppresses the immune system and thus makes them more vulnerable to cancer. However, the importance of cancer gene activation in an organ after death must be further analyzed.
Forensics also benefit from this discovery. The presence of activity in these surviving genes will be used to obtain a more precise indication of the time of death.
The results of the research show that the current concept of death may need to be revised, as the scientists wonder if mRNA activity could demonstrate that the organism is still struggling to regain balance.
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