Spanish scientists have successfully mapped the genome of a jellyfish species that can escape age-related death by reverting to a juvenile state after reaching adulthood.
In their study published on 29 August 2022 in the peer-reviewed Proceedings of the National Academy of Sciences, the team writes that they hope their findings may provide clues to a better understanding of human aging and the health conditions we face as we age.
T. dohrnii, nicknamed the immortal jellyfish, goes through a life cycle just like other species of jellyfish. In one of these stages, the jellyfish attaches itself to the seafloor as a polyp, essentially a stalk of tissue, and tries to stay alive. When the right conditions are ensured, they can reproduce asexually by cloning, eventually transforming into the jelly-like “medusa” form for which jellyfish are best known.
Once most jellyfish reach this adult “medusa” stage, they can begin to reproduce sexually by releasing sperm and eggs into the water. After this stage, the typical jellyfish would eventually die. However, the researchers said that T. dohrnii can reverse its aging process even after adulthood, reverting to a polyp on the seafloor.
To find out how T. dohrnii’s immortality works, the researchers compared its genome with its cousin Turritopsis rubra, which doesn’t have the same anti-aging ability. They said the T. dohrnii genome had twice as many copies of DNA protection and repair genes.
The team also discovered that the jellyfish has a unique mutation that allows it to prevent damage to telomeres, the protective caps on the ends of chromosomes. In humans, our telomeres tend to shorten with age.
Marine biologist María Pascual Torner, the study’s lead author, said that it is unlikely that humans will ever possess the same anti-aging ability as T. dohrnii. “It is a mistake to think that we will have immortality like this jellyfish because we are not jellyfish,” said the postdoctoral researcher at the University of Oviedo, according to the Journal. Still, the study findings could help us understand the mechanisms of aging in general; she said.