Genome Sequencing of the "Immortal Jellyfish"

Scientists in Spain have just recently mapped the genome of a certain species of jellyfish. However, this isn’t just news for the marine biology community interested in gelatin-like creatures. This particular species, Turritopsis dohrnii, aka “immortal jellyfish” can escape age-related death by returning to a juvenile state after reaching adulthood. Sparking the imaginations of immortality for many.

In their study published Monday in the Proceedings of the National Academy of Sciences, their findings clues toward furthering our understanding of the role genes play in human aging and well as uncover why species across the animal kingdom experience aging in unique ways… or not at all.?

In most species, cellular and molecular derangement conspire toward illness and susceptibility to disease and predation (for some) shortly after the reproductive phase. In humans, that translates to being about 50-55 years old. In this species, however, jellyfish can reverse its aging process even after maturing to full adulthood, returning to the pre-reproductive years. To make a very rough analogy, this would be like reverting to 8th grade around the time most parents become empty nesters or start their colonoscopy screening.?

In a bid to uncover the mechanisms of immortality, the researchers compared its genome to a “control” - a close ancestral relative lacking immortality (Turritopsis rubra). They discovered that T. dohrnii's genome had twice as many copies of genes associated with protecting and repairing DNA.

The team also found that the jellyfish had a unique mutation that allows it to prevent telomeres — the protective caps on the ends of chromosomes — from deteriorating. In humans, our telomeres tend to get shorter as we age and this shortening is associated with the onset of age-related diseases as the DNA loses this protection.?

So how does this impact human aging and longevity? We may find a handful of jellyfish genes similar to those in humans that may be worthy of further investigation. These findings could elucidate novel drug targets and mechanisms for preserving DNA and buffering the damage accumulated over time, but it would be a mistake to think we will have immortality like this jellyfish because we are not jellyfish. As you can probably imagine, the human form is just not conducive to “morphing” to different states and the overall translatability of such findings is relatively low.?

The good news:?As far-fetched and impractical as this “re-cycling” through life and developmental stages is for humans, it begs a fundamental question: Do people even want to live indefinitely or even long past the current limits? As it turns out, people’s ambitions around longevity are far more finite and within reach: roughly 91 years on average. For the most part, people aim to live healthier longer, extending the number of quality years over the absolute quantity of time and that is exactly what the foreseeable impact of breakthrough studies such as this one. However, it will be interesting to see how regenerative medicine and emphasis on healthy aging will impact preferences toward life expectancy. If you and your loved ones could live healthier and longer, wouldn’t that change your perceptions toward a 91-year life? I think it would.