Imagine a “person” who:
He has a heartbeat, body temperature, warm skin, lungs, liver, kidneys, and all vital organs.
Every aspect is just like a human, except for one thing: no brain.
He cannot think, does not know who he is, and even does not know he exists.
So can we consider him a “human”?
If we get a little more “evil”—is it unethical to use his organs for transplants?
What if we mass-produce such “brainless humans” specifically to harvest parts?
These three questions are not mere alarmist fears; they are part of a project seriously promoted by a Silicon Valley company that has secured billionaire investments.
(Related report)
In March 2025, three Stanford researchers published an article in MIT Technology Review titled, “Spare Human Bodies Obtained Ethically May Revolutionize Medicine.”
(Related paper)
In simple terms, the article introduces a concept called “bodyoid,” which refers to human bodies cultivated without brains, consciousness, or pain perception, using stem cells and gene-editing technologies for medical research and organ transplants.
Days after the article was published, Wired reported on a previously low-profile biotech company, R3Bio, which is actually commercializing bodyoids.
Moreover, R3 Bio calls their project not “bodyoid” but “organ sacks.”
In medical terms, “Organ sacks” refers to the membrane structures that encase and contain body organs.
However, in the current context, “Organ sacks” conveys a chilling indifference—
they are merely bags designed to harvest and store organs, not even bodies.
(Illustration)
Regarding this, R3 Bio co-founder Alice Gilman stated she dislikes the term “brainless humans” to describe “organ sacks,” saying:
“It doesn’t lack anything; we simply designed only the parts we wanted.”
The investors in this project are intriguing, primarily consisting of industry big shots.
One is a Singapore longevity fund, colloquially known as “Immortal True Dragon,” primarily investing in longevity and biotech projects.
(Immortal True Dragon’s official site)
The fund’s CEO stated in an interview, “If we can create an unconscious, headless body (bodyoid), it would be the best source of organs.”
Another investor is Tim Draper, the legendary Silicon Valley venture capitalist known for backing companies like Skype, Tesla, and SpaceX.
(Tim Draper)
Additionally, another participant is the UK-based LongGame Ventures, a venture firm.
What does “Longgame” imply? It implicitly suggests “longevity.”
Ultimately, this is due to the recent “longevity movement” embraced by Silicon Valley, with wealthy individuals like Bryan Johnson being ardent believers in the notion.
A group of superwealthy individuals believes life can be “hacked” and death treated as a solvable problem.
Very Silicon Valley-esque.
(Bryan Johnson)
Returning to the subject, the reason this is happening now is due to a realistic background: a movement against experimenting on animals is gaining momentum in the U.S.
In April 2025, the FDA announced plans to gradually eliminate animal testing requirements for monoclonal antibodies and replace them with AI modeling, organ chips, and other alternatives.
The FDA head described this as a “paradigm shift in drug assessment.” Soon after, the NIH also announced in July 2025 it would no longer fund new projects focused solely on animal testing.
Simultaneously, the supply of monkeys for experiments in the U.S. is facing a severe shortage.
At the beginning of 2020, China suspended exports of primates due to the pandemic, and previously, about 60% of the U.S.’s experimental monkeys came from China.
This ban has not been fully lifted, leading to a dramatic price increase for experimental monkeys of over 20 times at one point.
(Experimental monkey, illustrative)
In addition to the shortage of animals, animal rights organizations continue to apply pressure.
One of the seven primate research centers in the U.S. has already suggested considering transforming into an animal sanctuary. The CDC is also gradually reducing monkey research.
The shortage of monkeys, tightening regulations, and the emergence of alternative options present the backdrop for the “brainless human” project.
No matter how disturbing this sounds, “brainless humans” can indeed address actual pain points in society.
First is the issue of human experimentation.
Drug companies often develop new medicines that work well in mice but fail in humans; this is commonplace in the industry.
It’s estimated that about 90% of drugs that go through animal testing will fail during human clinical trials, resulting in significant monetary, energetic, and temporal losses. The biological differences between mice and humans are substantial, and even monkeys are not sufficiently similar.
Existing alternative options like “organ chips” (which simulate organ functions on microchips) are improving but still cannot truly mirror the complex human physical environment.
A “brainless human” with a complete body system could theoretically be the perfect test subject, at least much better than animals and chips.
(Illustration)
The second issue is the shortage of organs.
Currently, over 100,000 people in the U.S. are waiting for organ transplants, with an estimated 17 dying each day because they did not receive their organs in time.
Gilman’s father previously underwent heart transplantation, and in interviews, she mentioned that there is rampant organ trafficking in the underground markets of Asia and Africa, indicating a significant ethical need for organs.
In this area, academia has made considerable efforts, such as transplanting gene-edited pig organs into humans, but this technology is still far from mature.
In January 2025, a U.S. man received a gene-edited pig kidney transplant and successfully lived with it for 271 days. However, the pig kidney was eventually rejected and had to be removed, forcing him to return to dialysis while waiting for a matching human kidney.
(Man with pig kidney transplant)
If we can manually create human organs, wouldn’t these pain points be resolved?
However, can we consider “brainless humans” as safe to regard as “non-human”?
The ethical premise of everything R3 Bio is doing is: no brain = no consciousness = no moral issues.
Stanford bioethicist Hank Greely also stated in an interview that if a living being has no brain, “we can reasonably be assured it does not feel pain.”
But the issue is: the scientific community has no consensus on the origin and definition of “consciousness.”
Is the brain the only source of consciousness?
Greely himself acknowledged that everything “may never succeed, but it also may.”
The academic community has debates on this, as a paper published last November in the philosophy and technology journal by Springer (the Nature publisher) bluntly addressed the “Bodyoid” issue.
The paper primarily argues that even if the so-called “brainless human” could be realized technically, their creation would present new, larger, deeper ethical problems.
(Related paper)
Whether it is moral to harvest organs from severely brain-damaged patients is still contentious, so how could it be with “brainless humans”?
To take a step back, even if R3Bio can successfully cultivate brainless individuals, they would still have heartbeats; they would just need a ventilator to maintain life and look quite similar to patients who are brain dead.
They lie there, their appearance indistinguishable from ordinary humans. Just think about the ethical controversies that would arise.
The legal and ethical definitions surrounding brain-dead patients have sparked decades of debates within the medical and legal communities.
In contrast, bodyoids occupy an even more awkward gray area; while they never have “personality,” their “hardware” is human.
How do you legally define them? As biological materials? Or a form of “human”?
(Illustration)
Of course, all of this is still largely fantasy; we should say this is merely an over-exaggeration, as the so-called “brainless humans” are still far from realization.
Reports indicate that R3 Bio is currently utilizing animal cells.
According to Gilman, R3 Bio has already been able to create a mice-version of the “Organ Sack,” but she claims that R3 Bio has not truly produced “brainless mice.”
However, this is R3 Bio’s official stance.
Yet, Wired discovered that Gilman posted a job ad online seeking veterinarians in Puerto Rico for work involving “implanting embryos, monitoring pregnancies, assisting in childbirth…”
This raises the possibility that “Animal version of Organ Sack” has already emerged somewhere in R3 Bio’s lab…
(R3 Bio recruiting veterinarians)
In interviews with the media, R3Bio did not disclose the details of their technology, and when asked about how to scale up from mice technology to monkeys and humans, they simply stated they are exploring “a combine of stem cell technology and gene-editing.”
What does “combining stem cell technology and gene editing” mean? According to Paul Knoepfler, a stem cell biologist from UC, it probably means inducing pluripotent stem cells to differentiate while using gene-editing to disable brain development genes, allowing the stem cells to develop into an “Organ Sack” with organs but without a brain.
This all appears too chilling, but we shouldn’t be overly worried.
After all, creating an embryo is one thing, but raising the embryo to maturity is another matter.
(Illustration)
To have a “brainless human” serve as an organ donor, it first needs to grow into a substantial form which may take at least a decade.
Furthermore, since “brainless humans” lack brain stems and cannot breathe independently, during these years they would require ICU-level care, making the costs unlikely to be low.
This also means that if this technology is commercially viable, it cannot be artisanal but must be factory-produced at scale to lower costs. The factory would require legal validation recognizing it as a “product” before it can be built.
Therefore, it seems that within the next decade, the so-called “Organ Sack” is unlikely to materialize……
However, some scholars argue that precisely because it cannot be produced in the short term, we should discuss it now—waiting until it actually becomes a reality would be too late.
(Related paper)
This makes us think of Gilman’s statement: “It’s not about lacking something; we only designed the parts we wanted.”
But perhaps the real question is not what is missing, but what we might lose in the process of creating it…
ref: