NIH greenlights human-animal hybrid research

AUGUST 5, 2016

by Chuck Bednar

The US ban on research involving chimeras – human-animal hybrids developed by adding stem cells from a person into the embryo of a different species – could soon be at least partially lifted, according to a proposal released Thursday by the National Institutes of Health (NIH).

That proposal would lift the ban, which according to Nature has been in place since September of last year, in specific cases while also establishing a panel to review the ethics of projects that apply for grants. It would also reduce the time frame in which human cells can be introduced to non-human primate embryos to before the development of the central nervous system.

By doing so, the NIH hopes to limit the number of human stem cells which would become part of the chimera’s brain, the publication added. Furthermore, the new rules would any the breeding of animals with human cells to prevent a human-like embryo in the womb of a primate, and/or the birth of offspring that is closer to human than the creatures which gave birth to it.

“Biomedical researchers have created and used animal models containing human cells for decades to gain valuable insights into human biology and disease development,” explained Dr. Carrie D. Wolinetz, Associate Director for Science Policy at the NIH. “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.”

“With recent advances in stem cell and gene editing technologies, an increasing number of researchers are interested in growing human tissues and organs in animals by introducing pluripotent human cells into early animal embryos,” she added, noting that chimera research “holds tremendous potential for disease modeling, drug testing, and perhaps eventual organ transplant” but also raises “ethical and animal welfare concerns.”

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