CRISPR used to edit out sudden death gene mutations in major first

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Scientists could soon stop genetic diseases in humans before they are even born, according to an global research team that has successfully repaired faulty DNA in a live embryo.

The Ministry of Science and ICT said on Thursday that the researchers from the Institute for Basic Science (IBS) and Oregon Health and Science University (OHSU) used a new gene-editing technique and succeeded in correcting the mutated gene in human embryos which causes the heart disorder called hypertrophic cardiomyopathy.

"I think it's even more controversial now", Darnovsky said when asked whether the possibility of saving children's lives made the prospect of gene editing any less contentious.

But the new study, published in Nature, suggests that CRISPR might work as an aid to fertility clinic screening for risky inherited diseases, relying on a previously unknown ability of human embryos to swiftly fix their genes.

But the researchers say that method is expensive and hard on a mother. And how concerned should we be about the ethical implications of the technology?

Now, when it comes to using CRISPR to correct gene mutations in embryos, Mitalipov said Tuesday, "We've done some ground work".

When this technology is applied to "germ cells" - the sperm and eggs - or embryos, it changes the germline.

A pioneering technique to "fix" an embryo's faulty DNA was unveiled by scientists last night. Previously, scientists fertilized eggs and then added the CRISPR/Cas9 gene editor (top row). In Australia, the National Health and Medical Research Council has a strict set of guidelines, meaning that all research performed on human embryos is monitored very closely, and many limitations exist. But they found that their edits were imprecise.

Humans have two copies of every gene, but some diseases are caused by a mutation in only one of the copies. Previously, such experiments have been reportedly conducted in China. The National Academies of Sciences, Engineering and Medicine had allowed the research to continue, and had sent recommendations that were followed, the researchers said. In the designer baby-filled future Darnovsky is concerned about, the line between therapeutic and augmentative gene edits is blurred.

Wu said timing was key for preventing off-target effects and mosaicism. And gene editing procedures could also treat patients with sickle cell anemia, HIV, and multiple types of cancers including leukemia and breast cancer.

In the United States, there are various regulations and restrictions on how embryos can be edited, including stipulations that such work can't take place with taxpayers' money. The the efficiency of the process would have to be above 90%, he suggested, and more work needs to be done to absolutely show that CRISPR didn't really cause any collateral genetic damage to the embryos.

The objective: to cut the defective DNA to bring about its fix.

"It may be that some countries never permit germline genome editing because of moral and ethical concerns", said Professor Joyce Harper from University College London.

So what lies ahead for human embryo editing research?

Unlike earlier research in China, the OR team managed to get the repaired genes into every cell in 42 out of the 58 embryos that they edited. Their work was largely funded by private donations and university money.

Parents at risk of passing on genetic conditions to their children can only now prevent it with embryo screening.

Underlying this notion, in part, is the fact that prospective parents already genetically screen IVF embryos before deciding which ones to implant. And if used universally, it could eliminate many rare genetic diseases.

Though the scientists only edited out mutations that could cause diseases, it modified the nuclear DNA that sits right at the heart of the cell that also influences personal characteristics such as intelligence, height, facial appearance and eye colour. At this moment in time, designer babies are as hypothetical as extraterrestrial monsters. "The technology is not there yet. For numerous traits that people want in their next generation, there's not a single underlying gene". However, "no matter what anybody says, this is not the dawn of the era of the designer baby".

"All cells of the embryo were corrected", he said.

They also raise the ethical concerns worthy of a "brave new world" of Aldous Huxley. Under normal conditions, half of the man's children would inherit the gene, the disease and the risk for passing it on. The technology, which selectively "snips" and trims areas of the genome and replaces it with strands of desired DNA, has previously been used on adult humans and other species.

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