All five got pregnant. Researchers terminated the pregnancies of three of them to test the fetuses for chimerism, and they found it. Soon after, the remaining two monkeys delivered twins (named Roku and Hex for the Japanese and Greek words for "six") and a singleton, Chimero. All appear male, though testing on their cells reveals that they also contain individual female genomes.
Growing up chimeric
The monkeys were delivered by C-section. Their mothers rejected them, probably in response to the nonnatural method used to deliver them, so now they are being raised by a foster mama.
Researchers aren't yet sure whether Roku, Hex and Chimero will be able to reproduce. It takes rhesus macaques four to five years to reach sexual maturity.
There are no plans to create human chimeras and no need to, Mitalipov emphasized. This research by itself should help scientists in conducting biomedical research more relevant to humans, he said.
Chimeric mice, for instance, are used to produce genetically engineered "knock-out" mice that carry deletions of important genes. In that way, researchers can see firsthand what genes do or don't do.
The results may be useful in stem cell therapy, Mitalipov said. Researchers believe that stem cells cultured in Petri dishes could be transplanted into adult patients to treat conditions such as paralysis or Parkinson's disease.
"But this is based on mouse models," Mitalipov said. "We didn't know whether primates have this capacity."
The chimeric monkey study, reported today (Jan. 5) in the journal Cell, shows that primate cultured stem cells probably have some potential to differentiate, but they aren't comparable to in-vivo stem cells, or stem cells produced in the body, Mitalipov said.
"We cannot model everything in the mouse," Mitalipov said. "If we want to move stem cell therapies from the lab to clinics and from the mouse to humans, we need to understand what these primate cells can and can't do. We need to study them in humans, including human embryos."
Even though the researchers found success without culturing, cultured cells shouldn't be written off, said Richard Behringer, a geneticist at MD Anderson Cancer Center in Houston. The reason the cells didn't work in monkeys may be due to something in the laboratory process, not because of the cells themselves, Behringer told LiveScience.
"We know so little about the early embryology of our cells," Behringer said. "We know about the fertilization to the blastocyst stage because you can do that in vitro, but after that there's very little known about human embryology — this is when a woman may not even know she's pregnant. Having the monkey model is useful to understand the early embryonic development, where the monkey can stand in for the human."
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12 Comments
Add CommentWhat a beautiful story. It's heart-warming to see that these baby monkeys are being "cared for" by researchers in rubber gloves rather than their mothers in the wild. I'm sure living their lives in metal cages while being constantly experimented on is a delightful experience. I love the human race and the suffering we enjoy inflicting on other humans and the "lesser" animals.
Reply | Report Abuse | Link to thisI agree. Seven billion people. Are we an endangered species?
Reply | Report Abuse | Link to thisI agree, the extent of the exploitation is daunting. It's a brutal industry.
Reply | Report Abuse | Link to thisIf you don't grow your food and raise your own livestock (while treating it well throughout their lifespan), you're a gigantic hypocrite. You're also a hypocrite if you're using the majority of any technology today (take a look at some of the wars being fought in Africa over various metals and the atrocities that arise from such conflicts)
Reply | Report Abuse | Link to thisThis is a great discovery that will help further the human race, no matter what we do, we're going to have a negative impact on everything around us unless we all regress into farmers or hermits, though even then, other living beings will still suffer one way or another from our actions. At least any discomfort these animals feel will be for good reason.
Ok, reduce it to it's simplest form: Is an individual important? Is the species more important than the individual? Which species are more important than others? Is an individual of one species more important than the whole of another species? The whole question of the ethics of vivisection is just quicksand. Seems to me if you eat meat or wear leather or kill spiders from fear, you'd better shut up.
Reply | Report Abuse | Link to thisI don't think it helps to make it black and white, it has to be picking a spot on a spectrum... and people from different backgrounds with different views will all choose a different spot on the curve as the optimum spot. That's why these ethical discussions go round and round and round and never end or solve anything... there is no one exactly right solution.
Reply | Report Abuse | Link to thisPersonally I think the answer is to try and minimize suffering overall... sometimes it is better that individuals suffer to limit the suffering of others... sometimes the knowledge that we won't throw an individual under the bus, even to help the majority, ends up limiting the suffering of the majority in the macro sense.
Society benefits if we all feel secure that society values us as individuals, and society can benefit if we sometimes sacrifice and individual for the good of everyone else... but usually the benefit of the sacrifice is less than the feeling of security everyone gets from knowing they won't be sacrificed. The same ethic that protects indivual humans from being exploited for the good of everyone else, can be applied to animals... and if we break it too much for animals, it can feel like a step towards breaking it for people, which then harms everyone... but of course animals aren't humans, so that link between throwing them under the bus and throwing one of us under a bus isn't as strong. How do you choose which and when? Heh, everyone argues and disagrees and tells everyone else they are idiots, but I'd prefer some calm application of reason whenever possible.
I'd always tend to side with whoever seems to have really thought it all through, and did their best to balance all the conflicts in terms of least overall suffering for everyone... the answer may never be perfect, but siding with thinking carefully, over with knee-jerk emotional reactions, tends to be a winning rule of thumb for me.
Kinda Dr. Mengeleish or Frankensteinish to me. At one point do scientists draw a line on what is just too much with minimal benefit. Really these guys are not discovering anything, they are just goofing around with stuff, in this case stem cells and embryos and seeing what happens. What happens when one of these guys does make a human/cat/monkey chimera. Eventually one of these scientist will try.
Reply | Report Abuse | Link to thisIt is scary, daring stuff. Makes me uncomfortable. But if we can help heal the suffering of hundreds of thousands of people, maybe millions (thinking of childhood diabetes, Parkinson's disease...) maybe it is worth it.
Reply | Report Abuse | Link to thisthere are some people here who purport to read (and understand) these articles, but it is evident they do not understand very much at all. No one is asking them to run headlong 'over-the-cliff' (although, judging from their writings, they are already over the edge and on the way down), and no one is telling some tear-jerk story( (although one can almost hear these folks blow their nose because of the tears brought on by their imagination [and inner lack]), but these pseudo-science-readers are a real detriment to the useful purposes of research and progress.
Reply | Report Abuse | Link to thisPlease, some of you, go back to your soap-operas and romance novels, and please, please, don't have children
in fact, some of you really should do your duty and volunteer for some experiment to be conducted upon yourself; you have benefited enough and given too little in return - why? because you have lapped up the benefits of a good education, and the understanding you demonstrate does credit to no one
So, when we are going to create half-animal-half-human ancient gods? How long to wait for a date with a mermaid, Pan or Anubis? Is not it our ultimate goal? And what's the price?
Reply | Report Abuse | Link to thisIt is basic research like this one which have developed all of the vaccines, medications, surgical procedures that exist today. A scientist must justify their use of any model in their study in order to get the funding in the first place. The use of animals is a price we have to pay. Maybe you should write to our lawmakers to ease up on the use of human subjects or you should volunteer yourself to get tested on. Why bother reading this journal If you don't even support the work that these scientists spend years on.
Reply | Report Abuse | Link to thisIndeseo, you are quite right, these pseudo- scientists have no clue what the implications for these stem cell experiments are. One day this research will provide numerous health benefits, and possibly to the ones who commented on this article. Same thing happened with biotech, which developed through cancer, and other disease research. This in turn has led to advances in stem cell experiments.
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