Scientists in China want to conduct full-body transplants, which would replace every part of the human body, to help people who are paralyzed.

The New York Times reports that Dr. Xiaoping Ren, an orthopedic surgeon at Harbin Medical University in China who was involved in the first hand transplant in the U.S. in 1999, says he is building a team for the procedure and has so far tested the possibility in mice and cadavers. The mice only lived for a day after the transplant.

The science behind the procedure is still unclear, and many experts argue that it’s not possible to sever and reconnect a spinal cord. Others condemn the work on ethical grounds, calling it “reckless”. If the surgery failed, the recipient would die.

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According to the Times article, doctors say Ren’s idea for an operation is impossible:

His plan: Remove two heads from two bodies, connect the blood vessels of the body of the deceased donor and the recipient head, insert a metal plate to stabilize the new neck, bathe the spinal cord nerve endings in a gluelike substance to aid regrowth and finally sew up the skin.

The intended operation is also the latest in a series of scientific efforts by China that push ethical boundaries. In April 2015, it was announced that Chinese scientists used a genetic editing technology called CRISPR to modify human embryos, to the disbelief of researchers worldwide who believed the science was too nascent at the time.

[NYT]

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