Immortality does indeed exist… But to be immortal you have to be a special jellyfish, not a vampire. A type of cnidarian, Turritopsis dohrnii, is known to have found the secret to eternal life. Geneticists hope that comparing the DNA of T. dornii with its close relative, T. rubra, will help us understand the aging process and how to get rid of it.
Turritopsis is a half-centimeter long warm-water jellyfish. At least three hydra species, like Benjamin Button, have the capacity to age backward, then transition from adult to juvenile stage before regrowth. But two of them can only go back to childhood from the hydra equivalent of adolescence, once they reach adulthood, they are on an irreversible path again. But T. dohrnii appears to be able to transition from the free-floating adult stage to the bottom-dwelling polyp known as life cycle reversal (LCR) at will.
A paper published in the Proceedings of the National Academy of Sciences offers a comparison of T. dorhnii and T. rubra, in hopes that the differences will be illuminating, and also shows several more distantly related species of cnidarians.
from the Universidad de Oviedo, Spain. Maria Pascual-Torner and co-authors did not find a single genetic point that gives the secret to youthfulness. Instead, they discovered and reported a wide variety of potentially contributing differences: “We identified variants and expansions of genes associated with replication, DNA repair, telomere maintenance, redox environment, stem cell population, and intercellular communication.”
All of this may be important, but the study focused on two important aspects of T. dohrnii’s genome that were not found in its relative. One of them is silencing polycomb repressor complexes, i.e. 2 families of proteins that regulate gene expression. The other activates pluripotency – the capacity of a stem cell to turn into any type of cell it needs – during life cycle reversal.
Even assuming possible, their implementation in humans would certainly be an almost impossible task, similar to Hercules’ tests. However, while many features of T. dorhnii probably only work together, some may provide a few extra years in more complex creatures, including ourselves.
But even T. dohrnii cannot live forever unless a great miracle happens. This is because of the sad consequence of a small life form with little defense and prey to larger creatures. That’s probably why it’s so hard for them to come to dominate Earth as we would expect an immortal species to do.
Still, his capacity for rejuvenation indicates the theoretical possibility of eternal life.
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