Scientists sequence genome of elephant shark, say they have no bones

A new research has suggested that the elephant shark and its cousins are the world’s oldest-living jawed vertebrates on the Earth.

A team of researchers came to the conclusion after they conducted sequencing of the genome of the elephant shark and its cousins the sharks, skates, rays and chimaeras.

Elephant shark is a curious-looking fish with a snout resembling the end of an elephant’s trunk. Researchers said that the elephant shark was selected for sequencing among all the cartilaginous fishes because of its compact genome. It’s genome is one-third the size of the human genome.

elephant shark

While sequencing the genome, the researchers found that the Elephant shark’s skeletons are made of cartilage and not of bones. This makes them an odd member of vertebrates group.

“The genetic blueprint will help in understanding the evolution and diversity of bony vertebrates, including humans,” said senior author Wesley Warren, PhD, research associate professor of genetics at The Genome Institute at Washington University School of Medicine.

Researchers studied the elephant shark genome and compared it with other genomes. While analyzing the genome, the scientists found that a family of genes were absent in the elephant shark, which were usually present in all bony vertebrates. Moreover, it was also discovered that the elephant shark lacked special types of immune cells that are responsible for defence against viral and bacterial infections.

The research has been published in the journal Nature.

  • Cool.

  • Leonard Greene

    “While sequencing the genome, the researchers found that the Elephant shark’s skeletons are made of cartilage and not of bones”
    Sorry, but researchers have known for years, if not decades, that ALL sharks skeletons are made of cartilage and not of bones.

    • Theo Campbell

      Go look in the cushions of your couch, See what you find. Does the fact that your wife, kids, or visitors know they lost that 65cents in your couch take away from your discovery? lol. Let someone else experience the excitement of discovery. Don’t rain on their day LOL

      • Leonard Greene

        So when my great-grandfather landed on Ellis Island he had ‘discovered’ America? And I guess everytime I drive to Kentucky I have ‘discovered’ the Ohio River?
        Go look in a book. See what it says about analogy. Does the fact that most of the rest of the world understand what an analogy is take away from your inablity to construct a valid one?

        • Theo Campbell

          Now that was uncalled for, are you so small you must attack a stranger on the net? I was attempting to be humorous, nothing more. Get a life dude.

          • Leonard Greene

            Well that was the lamest attempt at humor ever. Get a clue dud.

          • Theo Campbell

            Leonard, you following me around?. careful you might get kicked out the honky club, they don’t take kindly to jungle fever

          • Leonard Greene

            Don’t worry Theo, you aren’t my type. I prefer people who aren’t ignorant and aren’t racists. Also I don’t belong to any such club, so no worry about being kicked out. But thanks for your concern.

          • Theo Campbell

            OMG, what are you talking about? Racist? ignorant? Wow dude, that’s kinda harsh, i know my joke was bad, but…. really?…..

          • Theo Campbell

            Mr. Leonard G.Honky, where you at? lol, did my wounded stick scare you off? lol.

    • Pinkar

      By physiology yes, but not from looking at a genome. Admittedly it is poorly worded.

      • Leonard Greene

        From some further reading at more scientifically oriented websites, it appears what they actually did was identify the missing gene that regulates the process of turning cartilage into bone.

  • John Hall

    Leonard correctly points out that all sharks have been known to be cartilageous and it is impossible and a bit laughable that this reported as discovered while sequencing their DNA.

  • Cassandra

    You already said the shark was one of the cartilaginous fishes, then you erroneously wrote that sequencing the genome allowed the scientists to “discover” the shark had no bones. Editing is in order…

  • xzx

    Ok, so how do they taste? Wow, you call this science reporting?

  • Charlie Cousins

    Looks a lot like a white sturgeon.