Jaws’s genome could reveal secrets to wound treatment, cancer suppression

Great white sharks are one of the latest animals to have their genome sequenced, meaning scientists now have access to the entire DNA code that makes the sharks the way they are, from their jagged, razor-sharp teeth to their thrashing, powerful tails.

Over roughly 400 million years, sharks have evolved in unique ways from other sea-dwelling creatures, like having skeletons made of cartilage rather than bone. The great white shark is one of the largest species of sharks, capable of growing up to 20 feet long. It can dive to depths of nearly 4,000 feet. It’s also quite long-living, with a lifespan of 70 years or more.

“Historically, there’s been a lot more interest in sequencing other vertebrates, like livestock and primates,” said study co-leader Michael Stanhope of Cornell University’s College of Veterinary Medicine. “But sharks have some fascinating biology going on that really warranted more investigation.”

Of particular importance to scientists is the great white shark’s superpower-like ability to heal from wounds, and the fact that it, like other long-lived large animals, has unexpectedly low cancer rates. Wired Magazine explains that you’d expect an animal with a big body — and therefore lots of cells in said body — living for a long time to be more likely to develop a cancer mutation — it’s simple math. In reality, it doesn’t play out that way.

The genome reveals insights into each of these traits.

Over the course of 400 million years, sharks have evolved a set of DNA sequences that create many massively efficient blood-clotting agents and scaffolding proteins that can build, and thereby heal, flesh faster than other animals.

“We found positive selection and gene content enrichments involving several genes tied to some of the most fundamental pathways in wound healing, including in a key blood clotting gene,” said Stanhope. “These adaptations involving wound healing genes may underlie the vaunted ability of sharks to heal efficiently from even large wounds.”

The genome shows that sharks have large DNA sections that stabilize the genome with DNA repair mechanisms, which also suppress tumors. Further studies are planned to test the capabilities of these DNA segments to protect from carcinogens.

“Genome instability is a very important issue in many serious human diseases; now we find that nature has developed clever strategies to maintain the stability of genomes in these large-bodied, long-lived sharks,” said Mahmood Shivji, co-leader of the study and director of the Save Our Seas Foundation Shark Research Center. “There’s still tons to be learned from these evolutionary marvels, including information that will potentially be useful to fight cancer and age-related diseases, and improve wound healing treatments in humans, as we uncover how these animals do it.”

Neogen doesn't specialize in shark genomes, but we do offer genomic testing for livestock and companion animals. Check out our website for more information.