- HEAVEN/GEMINI International Collaborative Group, Turin, Italy
HEAVEN/GEMINI International Collaborative Group, Turin, Italy
DOI:10.4103/2152-7806.190473Copyright: © 2016 Surgical Neurology International This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.
How to cite this article: Canavero S, Ren X. Houston, GEMINI has landed: Spinal cord fusion achieved. Surg Neurol Int 13-Sep-2016;7:
How to cite this URL: Canavero S, Ren X. Houston, GEMINI has landed: Spinal cord fusion achieved. Surg Neurol Int 13-Sep-2016;7:. Available from: http://surgicalneurologyint.com/surgicalint_articles/houston-gemini-landed-spinal-cord-fusion-achieved/
Keywords: Gemini, head transplantation, heaven, peg, spinal cord fusion
In June 2013, the world was taken by storm by the announcement that a full head (or body) transplant was possible.[
Despite several publications delineating the rationale of the GEMINI protocol over the past 3 years,[
Today, it is most gratifying to announce a series of proof-of-principle papers that will dispel that hysteria once and for all.
One of the keys to a successful spinal cord fusion is a very sharp cut that minimizes damage of the cord, both at the white matter and the gray matter level. This allows the two interfaces of a severed cord to regrow neurites out of the gray matter core, the vital component of the sensorimotor machinery that makes us move and feel (the so-called cortico-trunco-reticulo-proprio-spinal pathway, CTRPS) – unlike the previous misbegotten dogma that the white matter (including the pyramidal corticospinal fibers) with its 20 million fibers was solely or to a large extent in charge of these functions (for in-depth anatomical discussion, see references 2–3 and 6). Work done since Cajal's time, but then forgotten or ignored, made it clear that a sharp cut was not irreversibly associated with permanent paralysis; in fact, animals reacquired sensorimotor function.[
A sharp cut has been equated to standard spinal cord injury, which is to a large extent unrecoverable because of the widespread mechanical disruption of the cord's cell bodies and extensions, along with the formation of cysts and scars. This is a major conceptual error. The degree of mechanical disruption is fractional in sharp sections. It is true that a scar, however limited, forms after a sharp severance, but we know that a scar is no obstacle to regrowing neuritic extensions from the spinal propriospinal neurons. This fact was shown by US neurosurgeon W. Freeman more than half a century ago, and rediscovered in 2016![
Original histological frames from Freeman 1963: Notice profuse regrowth across the point of full severance of fibers piercing the scar (rat, dog, and primate) (silver staining). In addition, notice recovery of impulse conduction and Freeman with a close-to-normal dog at 7 months (see references 2–5) (*: point of sharp section; **: scar; +: Regrowing fibers)
On the other hand, this recovery process takes time and a patient receiving a new body must be able to move and feel as fast as possible, ideally within days or a few weeks at most.
Enter the second pillar of the GEMINI spinal cord fusion protocol; fusogens, and in particular polyethylene glycol (PEG).[
Ever since 2013, one of us (Canavero) has collaborated with Prof. Kim in Seoul, Korea, a veterinarian scientist who first offered to investigate GEMINI in animal models. That effort paid nice dividends now displayed in full in this journal. Kim first showed that PEG applied to a sharply severed cervical spinal cord accelerated the initial recovery of motor evoked potentials (MEPs) in mice within the first hour, with occasional voluntary movements at 1 week.[
Early this year, one of us (Canavero) was approached by Prof. J. Tour's PhD student William Sikkema at Rice University's Faculty of Chemistry and Nano Center in Houston, Texas, offering to test a “nano-enhanced” form of PEG (Texas PEG). Prof. Kim with his team immediately tested it. The initial results are indeed nothing short of miraculous.[
While of course these results are in need of duplication, there can be no doubt that this new batch of data confirm that a spinal cord, once severed, can be refused with useful behavioral recovery. Certainly, it will be necessary to confirm the absence of toxicity of TexasPEG in further studies, although, given the small amount used topically, it is very difficult that any significant toxicity is observed in the long term. Last but not least, the astute reader of these papers will have noticed that these animals developed no pain-related behaviors nor signs of possible “full body phantoms.”
How PEG accelerates the GEMINI fusion process is discussed elsewhere.[
Kim brilliantly chose for a model of a stab wound a sharp severance to the cervical cord in a dog where more than 90% of the cord was cut.[
It is up to neurosurgeons to find now a way to apply this in patients. While stab wounds are rare, traumatic spinal cord injury is not. Freeman already suggested a way to cure spinal cord injury: Remove the injured segment, perform a vertebrectomy, bring in contact the two stumps and wait [
What comes next on the path to the first HEAVEN surgery?
Despite these exciting animal experiments, the proof of the pudding rests in human studies. The only ethical – and expeditious – way is to test GEMINI in brain dead organ donors before explantation during a 6-hour window during which the cord is severed, PEG applied, and motor conduction assessed distally. The same rationale applies to peripheral nerves (phrenics, vagi).
Once the first impulses are recorded crossing the fusion interface, we will know that a human head transplant can materialize. At that point, the final testing of the HEAVEN hypothermia protocol will be necessary. In the meantime, extensive cadaveric rehearsals will train the surgical crews for the defining event of the 21st century.
1. Canavero S. HEAVEN: The head anastomosis venture project outline for the first human head transplantation with spinal linkage (GEMINI). Surg Neurol Int. 2013. 4: S335-42
2. Canavero S. Head transplantation and the quest for immortality. Amazon CreateSpace IP. 2014. p.
3. Canavero S. The “Gemini” spinal cord fusion protocol: Reloaded. Surg Neurol Int. 2015. 6: 18-
4. Canavero S. Commentary. Surg Neurol Int. 2015. 6: 103-
5. Canavero S, Ren XP, Kim CY, Rosati E. Neurologic foundations of spinal cord fusion (GEMINI). Surgery. 2016. 160: 11-9
6. Canavero S, Ren XP. The Spark of Life: Engaging the Cortico-Truncoreticulo-Propriospinal Pathway by Electrical Stimulation. CNS Neurosci Ther. 2016. 22: 260-1
7. Estrada V, Brazda N, Schmitz C, Heller S, Blazyca H, Martini R. Long-lasting significant functional improvement in chronic severe spinal cord injury following scar resection and polyethylene glycol implantation. Neurobiol Dis. 2014. 67: 165-79
8. Kim CY. PEG-assisted reconstruction of the cervical spinal cord in rat: Effects on motor conduction at 1 hour. Spinal Cord. 2016. p.
9. Kim CY, Oh H, Hwang IK, Hong KS. GEMINI: Initial behavioral results after full severance of the cervical spinal cord in mice. Surg Neurol Int. 2016. p.
10. Kim CY, Sikkema WK, Hwang IK, Oh H, Km UJ, Lee BH. Spinal cord fusion with PEG-GNRs (Texas PEG): Neurophysiological recovery at 24 hours in rats. Preliminary results. Surg Neurol Int. 2016. p.
11. Kim CY, Hwang IK, Jang SW, Kim HS. Accelerated recovery of sensorimotor function in a dog submitted to quasi-total transection of the cervical spinal cord and treated with PEG. Surg Neurol Int. 2016. p.
12. Liddelow SA, Barres BA. Regeneration: Not everything is scary about a glial scar. Nature. 2016. 532: 182-3
13. Ye YJ, Kim CY, Miao Q, Ren XP. Fusogen-assisted rapid reconstitution of anatomophysiologic continuity of the transected spinal cord. Surgery. 2016. 160: 20-5
Posted December 13, 2017, 1:31 pm
What was the “accidental mishap” with the rats? Did someone drop them?
Posted April 16, 2019, 5:52 pm
Are you able to repair a brachial plexus injury? Avulsions of C5-6 through T1 based on MR findings. Interestingly however he has near normal function of C5 excellent function of supra and infraspinatus and deltoid, as well as substantial but weak elbow flexion and, grade Elhassan believes it to be a 4. Normal trapezius and horner syndrome.
Posted July 6, 2021, 2:29 pm
but what will be the tissue shrinking effect of severed cords due to elasticity ?