The U.S. National Institutes of Health (NIH) announced on Thursday new guideline proposals for human-animal hybrid or chimera research. The announcement came as news emerged that the agency was considering lifting a moratorium on the funding of chimera research that involves inserting human stem cells into animal embryos to create chimeric embryos that may develop into organisms that are partly human and partly animal in bio-genetic constitution.
The NIH had imposed moratorium on chimera research due to ethical concerns raised. The NIH’s 2009 guidelines had banned funding of research involving insertion of human stem cells into animal cells. The agency announced in 2015 that it would not lift the ban until new comprehensive guidelines were in place.
Although human-animal hybrid research is widely considered of tremendous potential value, ethical concerns raised have forced caution about proceeding with the funding of ground-breaking research in the field.
The new NIH proposals are designed to take care of the ethical concerns ahead of lifting of ban on funding of future projects.
NIH said that with new advancements that have extended possibilities in the field of chimera research, it had become necessary to consider lifting the moratorium, but comprehensive policy guidelines would have to be put in place that will ensure funding is restricted to certain categories of research projects to create chimeras.
The proposed restrictions extend to even earlier embryo stages that are currently covered.
Special care is being taken in the use of non-human primate embryos in chimera research because primate species are very closely related to humans.
However, the proposed policy guidelines will lift the moratorium on funding of experiments involving other non-human species except in cases where the expression of human traits is relatively pronounced.
The guidelines are designed specifically to prevent a situation where researchers knowingly or unknowingly create human-like embryos in the lab. Thus, the insertion of human stem cells into rodent embryos will be allowed because it is scientifically impossible to create human-like chimeras using rodent embryos.
The need to ensure carefully controlled and monitored chimera projects under strict policy guidelines is particularly relevant in experiments designed to study the development of neurological degenerative diseases of the human brain, such Alzheimer’s and Parkinson’s diseases, which require creating human brain cells and tissues.
The worst-case scenario in Chimera research is the sci-fi scenario in which a mad scientist decides to create an animal that is essentially a cross between a human person and an animal. A more specific version of the worst-case scenario imagines a situation where a scientist creates an animal with a human brain that has human-like thought powers and consciousness.
But it is understood in the scientific community that extreme scenarios where researchers create a real human-animal is ethically unacceptable and that it is unlikely that any researcher would stray that far. What the current guidelines focus on instead are ethical issues that may arise in situations where scientists inject human stem cells into animal embryos for the purpose of studying the development of different organs and tissues. Such experiments could help scientists to model the development of human diseases with the goal of discovering new ways to prevent them.
Scientists hope that chimera research would lead to the ability to grow organs for surgical transplants in the laboratory. For instance, it might be possible in the future to raise pigs that can produce human organs — such as kidneys, livers and hearts — that can be used for transplant surgery.
The NIH explained the decision to allow rodent embryos to be used in human-animal chimera research.
“Human tumor cells are routinely grown in mice to study cancer disease processes and to evaluate potential treatment strategies,” the statement said. “To advance regenerative medicine, it is common practice to validate the potency of pluripotent human cells — which can become any tissue in the body — through introducing them into rodents.”
“I am confident that these proposed changes will enable the NIH research community to move this promising area of science forward in a responsible manner,” Carrie D. Wolinetz, associate director for science policy at NIH, said.
“It’s very, very welcome news that NIH will consider funding this type of research,” Pablo Ross, an expert at the University of California, Davis, said. “We need funding to be able to answer some very important questions.”
But critics have attacked the latest proposals, saying the safeguards are insufficient and can be circumvented by researchers. Some bioethicists worry that the proposed guidelines do not foresee the creation of organisms that do not fall into the categories covered in the guidelines, Nature reports.
“If the predictions are wrong and the safeguards are not enough, then the price will be the cost of our humanity as well as these new life-forms that did not ask to participate in this frightening enterprise,” a critic commented.
But while critics worry about the ethical implications and the possibility of circumventing the guidelines through emergence of new categories of life-forms, some research biologists are worrying that the guidelines could restrict progress of research or fail to keep up.
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