https://www.sciencemag.org/news/2021/04/studies-make-brainlike-structures-or-add-human-cells-animal-brains-are-ethical-now
https://archive.is/mMuGG
Studies that make brainlike structures or add human cells to animal brains are ethical, for now, panel says
Experiments that create tiny brainlike structures from human stem cells or transplant human cells into an animal’s brain have made some scientists, ethicists, and religious leaders uneasy in recent years. And the National Institutes of Health (NIH) has restricted some of this research. Now, a U.S. scientific panel has weighed in with advice about how to oversee this controversial and fast-moving area of neuroscience.
The panel finds little evidence that brain “organoids” or animals given human cells experience humanlike consciousness or pain, and concludes current rules are adequate for overseeing this work. But they caution that could change, particularly as experiments move into nonhuman primates. “The rationale for the report is to get out ahead of the curve,” says Harvard University neuroscientist Joshua Sanes, co-chair of the National Academies of Sciences, Engineering, and Medicine committee that released its report today.
The report was requested by NIH, together with the Dana Foundation, which funds neuroscience research. It arrives as NIH ponders whether to lift a moratorium on funding chimera experiments—studies that create animals carrying human tissues or cells—that has been in place since 2015, even after NIH announced it would be lifted. The moratorium on chimera research suspended not only brain studies, but also projects that aim to grow organs for transplantation in pigs and sheep.
“We hope [NIH] will use the report to think through the issues,” says co-chair Bernard Lo, an ethicist and emeritus professor at the University of California, San Francisco (UCSF).
The committee examined three types of experiments: those that create neural organoids, tiny clusters of human brain cells in a dish sometimes called minibrains; those involving neural transplants, which add human cells to the brains of animals; and those that create chimeras, a type of transplant in which stem cells from one species are injected into the early developing embryo of another. Such experiments have raised concerns that the animals or organoids may have primitive forms of consciousness or feelings.
These experimental systems are “powerful models” for studying the human brain and identifying disease treatments, and there are ”strong moral arguments in favor of” this research, the report finds.
But the committee concluded organoids aren’t capable of consciousness because they lack the many cell types and connected structures of a brain. Even recent organoid experiments that claimed to detect brain waves similar to those in a fetus found “relatively nonspecific” signals, Sanes says—the panel didn’t find this work ethically troublesome. “It is extremely unlikely that in the foreseeable future” organoids will be conscious or feel pain, the report concludes. They “have no more moral standing” than other cultured neural tissues and require no new oversight.
The 11-member panel, which included ethics and legal experts, came to a similar conclusion about neural transplants because human brain cells mature more slowly than those of the animals, so can’t influence brain circuitry. And rodent chimera embryos containing human brain cells don’t survive long enough to have altered cognition or social behavior. However, monkey embryos containing human neural cells could develop to a stage that raises concerns, the report says.