If you’re looking for a rumored “fountain” of youth, you might want to start your search where there’s water, right? While that didn’t help Juan Ponce de León, Norwegian researchers went deep into the Atlantic to search for 400-year-old Greenland sharks whose DNA may hold a secret to their long lives … and possibly give some clues on how human life can be extended as well. Don’t worry – no sharks were harmed in the making of the study or this story. However, to be on the safe side, don’t tell Peter Thiel.
‘This is the longest living vertebrate on the planet … we are currently sequencing its whole nuclear genome which will help us discover why the Greenland shark not only lives longer than other shark species but other vertebrates.”
At the Fisheries Society of the British Isles symposium held this week at the University of Exeter, Professor Kim Praebel of the University of Norway revealed details on his team’s work with Greenland sharks (Somniosus microcephalus). Also known as the gurry shark or grey shark, Greenland sharks are North Atlantic and Arctic Ocean relatives of Pacific and southern sleeper sharks. The lifespan of these huge sharks – they can reach up to 7.3 m (24 ft) in length and weigh over 1,400 kg (3,100 lb) – is estimated to reach at least 400 years. In addition to their size, one reason for their long lives is that the depths at which they swim forces them to have a high concentration of trimethylamine N-oxide in their tissues, which makes their meat toxic.
Praebel’s team caught the sharks using lines, took tiny clippings from their skin and tagged them before releasing the massive sharks back into the ocean. Using those samples, they have sequenced the mitochondrial DNA from almost 100 Greenland sharks, giving them valuable data on their cellular energy. The next step is to do the same for DNA from the cell nucleus where the potential ‘fountain of youth’ genes are stored.
While Silicon Valley billionaires are waiting for that information, Praebel pointed out that an equally important aspect of this Greenland shark research is to study how being alive for the past 400+ years affected them. The researchers want to know where these sharks may have migrated from, how they developed differently than their relatives, what effect pollution had on them, how have their numbers been reduced by commercial fishing of their food supply and … of course … how have they been affected by climate change.
Finally, the researchers will be looking to solve the mystery of where and how the Greenland sharks reproduce … and how they keep the spark going after 300 or so years.
Again, no sharks were harmed in the study and eating them is extremely dangerous. Icelanders have been known to consume small quantities in a dish called kæstur hákarl, but only after the meat is boiled several times, buried in dirt for 6-8 weeks and then hung in strips to dry for several months. Mmm. Even after forcing down as much kæstur hákarl as they can stand, Icelanders have the same lifespan as other humans.
If that’s not enough to keep immortalists like Peter Thiel away, Inuit folklore says the first Greenland shark was born out of a cloth soaked with an old woman’s urine and they now live in the urine pot of Sedna, the goddess of the sea, which gives their flesh its high urea content and urine smell.
Who wants to live 400 years if everyone around you is holding their noses?