This browser is supported only in Windows 10 and above.

Human Limb Regeneration Is No Longer Just a Job for the Men in Black


Scifi characters are fairly adept at re-growing their limbs: Wolverine constantly recovers from amputations; Jeebs in Men in Black can get his head blasted off  and have a new one in place in a few seconds with only a mild headache; and Terminator 2‘s T-1000 can take repeated blows to the head and body like pebbles being dropped into a pond (provided he’s not himself dropped into molten metal). In real life, we’re not so lucky. A human being can re-grow a fingertip if its amputated above the first joint, but that’s about it… unless of course the Center for Regenerative Therapies in Dresden, Germany has their way.

Scientists abroad are studying a rare breed of Mexican lizard, the axolotl salamander, which may hold the key to human limb regeneration. Salamanders are well known for their ability to re-grow limbs after amputation, but the axolotl has the ability to regenerate jaws, skin, organs and parts of its brain and spinal chord, and do so at a much faster rate than normal salamanders. When an axlotl is injured, its wound is quickly covered with a stem-cell like growth, out of which sprouts the replacement body part.

“Humans do repair tissue but they don’t repair it perfectly,” says Elly Tanaka, one of the researchers at the Center. “The axolotl under certain injury conditions can go into kind of a mode where they repeat the process of the embryo.” Tanaka has genetically engineered a pigmentless strain of axolotl and inserted a glowing green gene from a jellyfish to witness the process of regeneration up close. Clearly, she’s never seen Godzilla, or she’d be aware of the consequences of injecting lizards with radioactive green stuff.

OK, so lizards can do it and aliens can do it. But how close are humans to regrowing our limbs? Scientists at the Center are mapping the genome of the axolotl, which is ten times larger than the human genome in the hopes of mapping the trait and transferring it to human beings. Tanaka and her team are confident, claiming they’ll be able to insert the trait in humans in under two decades. The Department of Defense shares their optimism, and has allocated $6.25 million towards their research in anticipation of healing wounded vets.

Of course, if scientists continue down this path, they’d be wise to heed the lessons of Spider-Man‘s Dr. Curt Connors, who’s been in the background of the first three Spider-Man movies and will (reportedly) be playing a large part in the fourth. Played by Dylan Baker, Dr. Connors is Peter Parker’s one-armed professor who ends up experimenting with reptile DNA to re-grow his lost appendage, and turns himself into a monstrous, human-sized Lizard that terrorizes New York. Will experiments with the axolotl lead to superhero fights and madness? Perhaps not, but Tanaka should at least be aware of any unusual mood swings when she gets to the human testing stage.

In the meantime, machines from the future and aliens from other galaxies appear to have cornered the limb-growing market. So until Tanaka and her team unlock the secrets of the axolotl, call the Men in Black and try your best to hold onto your butts.

Read More