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In a world first, UK scientists just got approval to edit human embryos

A human embryo.
A human embryo.

Scientists in Britain just got approval to conduct research that involves editing the genetic material of healthy human embryos.

This is a big deal: The UK's Human Fertilisation and Embryology Authority is the first government agency in the world to endorse research that involves altering the human genome for research — a move that could signal broader acceptance for a promising (but controversial) new area of science.

The research team, led by Dr. Kathy Niakan at the UK's Francis Crick Institute, is trying to better understand which genes allow a healthy human embryo to develop. Niakan’s team will use a promising new technique, known as CRISPR/Cas9, to edit genes that are active following conception. They'll then stop the experiments at day seven and destroy the embryos (so that they can't be used to start a pregnancy).

The hope is that this gene hacking could help researchers better understand what causes miscarriages and infertility — and perhaps one day lead to better treatments for infertility.

If Niakan's application gets approval from an ethics board, the research could start within months. But editing the human genome using CRISPR has not been without its critics.

CRISPR is a technique to "perform microsurgery on genes"

crispr Gene silencing and targeting with CRISPR. (Science in the News, Harvard)

Gene silencing and targeting with CRISPR. (Science in the News, Harvard)

To understand why today's news is a big deal, you have to understand the revolutionary technology that makes it possible.

CRISPR/cas9 — or CRISPR, as it's known — allows researchers to edit, cut out, and replace genes in any animal more quickly and efficiently than any form of genetic editing that's come before.

This technology could allow us to better understand our biology and how certain diseases work. One day, perhaps, it might even allow us to erase horrible diseases right out of the human genome.

Even more fantastically, it's at least theoretically possible to use CRISPR to hack the human race — to design humans that look or speak a certain way or that have resistances to certain diseases. That said, this possibility is still years away, and creating such "designer babies " remains illegal in the UK, the US, and most other countries.

This is the first time a government has approved embryo alterations

In 2007, researchers learned how to harness CRISPR to protect yogurt bacteria. By 2012, they were experimenting with this technique in test tubes. The next year, scientists around the world were using the technique to manipulate the genetic material of various animals, from mice to zebrafish.

Then came the big news. On April 18, 2015, scientists at the Sun Yat-sen University in China published a dramatic new study in the journal Protein & Cell. They had used CRISPR to edit the DNA of '"nonviable" human embryos (that is, embryos that couldn’t develop into humans).

Their goal? To use CRISPR to replace a gene in the embryo that is known to cause a serious genetic blood disorder called beta thalassaemia. In other words, they were trying to wipe out the inherited disease from the human embryo.

Unlike the newly approved UK research, however, those researchers in China never got approval from a government committee — only a university ethics board. And they weren't using healthy embryos, which Niakan plans to do.

There are still serious social and ethical issues related to CRISPR

The Chinese study on human embryos sparked a major debate about the ethics of CRISPR.

First, many researchers think it would be unsafe to use modified embryos to make an actual human — at least without much, much more research. "The stakes are enormous," wrote Stanford's Hank Greely, who specializes in the ethical and social implications of new biomedical technologies:

"You’d have to be criminally reckless, or insane, to try to make a baby this way unless and until we’ve had a decade or more of preliminary research, with human tissues and with non-human animals (including certainly primates and maybe even some of the non-human apes), showing that it is safe. If the moral risk isn’t enough of a deterrent, the potential legal liability should be."

The National Institutes of Health's Francis Collins was more pointed with his concerns about the ethics of human gene editing — particularly the question of whether we are ready to make new human babies who have no say over having their DNA altered.

"The concept of altering the human germline in embryos for clinical purposes has been debated over many years from many different perspectives, and has been viewed almost universally as a line that should not be crossed," he wrote in a statement.

That's because of "serious and unquantifiable safety issues, ethical issues presented by altering the germline in a way that affects the next generation without their consent, and a current lack of compelling medical applications justifying the use of CRISPR/Cas9 in embryos."

For these reasons, he said, the NIH won't fund genomic editing technologies involving human embryos.

To be clear, research like Niakan's is legal in the US — remember, it's not being used to start a pregnancy — but it won't be funded by the NIH.

Scientists have agreed it's okay to use CRISPR in the lab — but not to edit the human race

The Chinese research, and all of CRISPR's potential, spurred researchers to get organized about the ethical issues related to this line of inquiry.

In December, the National Academy of Sciences came out with a consensus statement about gene editing.

The document reflects the excitement and wonder of the new technology, but it also called for a slowdown on research involving hacking the human genome in ways that could be passed down to future generations.

Specifically, the statement drew the line at clinical research that involves editing the human "germline" — or the DNA of sperm, eggs, and embryos that could be inherited by future generations. Such editing could involve, for instance, taking an embryo, altering DNA related to a genetic disease, and then using that embryo to establish pregnancy and seeing whether that disease is indeed deleted from that person and her children.

They also argued that it's okay to use germline cells or early human embryos in basic and preclinical laboratory research — as long as they're not then used "to establish a pregnancy." And that's just what the new UK research would do.

No designer babies anytime soon

While much of the public's fascination with CRISPR seems to relate to its potential to create designer babies, researchers seem to agree that there's much to learn before that's even possible.

"The technology is clearly moving very quickly," Jennifer Doudna, one of the CRISPR inventors, said. "But I think the reality is we don't understand enough yet about the human genome, how genes interact, which genes give rise to certain traits, in most cases, to enable editing for enhancement today." Still, she added: "That’ll change over time."