Why a Chinese gene experiment is causing firestorm of controversy



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A Chinese scientist has rocked the world of genetics with claims Monday that I have used gene-editing technology to alter the DNA of embryos that have now produced twin girls. The experiment to try to make the babies resistant to HIV infection has been widely condemned as unethical, and under the controversial surrounding this cutting-edge science. Here's a first on what the fuss is about.

What is gene editing, anyway?

This is technology that – as the name suggests – can change the genetic building blocks of life by adding or subtracting material at various locations in the genome. The development of a new editing tool – CRISPR-Cas9 – has made the process easier, more precise and cheaper, generating much scientific excitement. But you're wondering, what does that acronym stand for (assuming it's nothing to do with fried chicken)? Clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9. You asked!

Why the excitement?

The enthusiasm stems from gene editing as potential to help better understand diseases, and to prevent or treat certain illnesses. Studies have focused on genetic ailments such as cystic fibrosis, hemophilia and sickle-cell anemia, but it may also have application to more complex illness like cancer, heart disease and HIV. In fact, treatments involving some diseases are now in clinical trials. In simple terms, the idea is to change the genetic content of cells as a disease in a living person is halted or prevented, or so it is not passed on to future generations.

In this Oct. 9, 2018 photo, Lin Zhitong speaks during an interview in Shenzhen in southern China's Guangdong province. Chinese scientist He Jiankui claims he made the world's first genetically edited babies: twin girls whose DNA he said he altered.

Mark Schiefelbein / AP Photo

Why is it controversial?

Much of the research is focused on laboratory and animal testing, since the safety of gene editing on human beings has not been confirmed. The main thrust of human study is addressing disease in "somatic" cells, those that can not be inherited. Altering the genes in germ cells – like those in sperm and eggs – is what raises major ethical questions. One fear is that the technology could be used to produce enhanced, human-like human beings, by programming facial appearance, height or intelligence levels, though some scientists doubt that it is technically possible.

Much of the research is focused on laboratory and animal testing, since the safety of gene editing on human beings has not been confirmed

Is it safe?

Another concern is about possible harmful side effects from gene editing, such as "off-target" errors where the edits occur in the wrong place, or "mosaicism," where some cells have the edit but not others. Some experts argue that until those safety issues are resolved, the potential harms outweigh the benefits of altering the genome of an embryo – a future human – as opposed to someone who already has or will have a serious disease. That is at the core of why the Chinese project – which purports to have changed genes to prevent the resulting person from ever getting HIV – is being condemned. "If true, this experiment is monstrous," Oxford University ethics professor Julian Savulescu told the Guardian newspaper.

In this Oct. 9, 2018 photo, Zhou Xiaoqin places an embryo in its storage tube into a liquid nitrogen bath after its removal from cryostorage at a laboratory in Shenzhen in southern China's Guangdong province.

Mark Schiefelbein / AP Photo

A security danger?

The U.S. intelligence community's official threat assessment has raised the prospect of unregulated gene editing being used to produce harmful biological agents. "Its deliberate or unintentional misuse might lead to far-reaching economic and national security implications," said the community's 2016 report to Congress.

Some Canadian researchers and ethicists are calling for Canada to loosen their rules, so basic research on germ cells can take place here

What is the law around gene editing?

About 40 countries have some kind of law or regulation at least discouraging the type of experiments done in China, where gene-edited embryos are actually implanted in mothers. Canada has one of the most stringent laws, making it a crime – with punishment up to $ 500,000 fine and 10 years in prison – to any gene editing on germ cells, even if they will not be used to create a new life.

Does everyone agree on strict legal bans?

Some Canadian researchers and ethicists are calling Canada to loosen their rules, so basic research on germ cells can take place here. "Our policy has simply shut down discussion," McGill University health-policy expert Bartha Knoppers said at a conference last year of Canada's Stem Cell Network.

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