July 3, 2022

Cures from therapeutic cloning “distant at best”, says Nature

The feverish excitement surrounding therapies from stem cells from cloned human embryos needs “a dose of reality”, says a Nature news feature. The recent announcement that a British team will soon begin therapeutic cloning has raised hopes of individualised cures for degenerative diseases. “In reality, say those in the field, such a prospect remains distant at best,” Nature comments.

Researchers in human embryonic stem cells distinguish between short- term and long-term benefits. The short-term benefits are insights into diseases such as diabetes and Parkinson’s. But because of the enormous obstacles that must be overcome, cures are a long-term benefit. For one thing, cloning is terribly inefficient. The South Korean team which announced earlier this year that it had created cloned embryos used 242 eggs from 16 women and produced a single stem cell line. “Until the success rate is improved, cures or treatments from therapeutic cloning will be impossible,” says Nature. Improving the efficiency of the technique will require repeat trials, but “fewer than five labs around the world” are working on it.

This pessimism about the short-term benefits of embryonic stem cell research was echoed by a researcher at a US stem cell research symposium sponsored by Mount Desert Island Biological Laboratory and The Jackson Laboratory. Dr Louis M Kunkel, director of the genomics program at Children’s Hospital Boston, reminded his colleagues that cures from stem cell research could be decades away. He recalled telling friends that a fund-raising telethon for muscular dystrophy would no longer be necessary after a medical breakthrough in 1990. “I can’t believe I ever said that,” he lamented. “We really can’t mislead the public about where these things are and what it’s going to take. It’s going to take a long time.”