Bioethicist: History Tells Us CRISPR Fears Are Overblown

Marcia Frellick

November 03, 2017

History tells us that fears about designer babies are exaggerated when it comes to the alteration, deletion, or swapping of genes in human embryos, renowned bioethicist Alta Charo, PhD, said during a TEDMED 2017 talk in Palm Springs, California.

Dr Alta Charo

"In fact, we've now had 50 years of responsible and useful advances in genetic screening, genetic testing and, most recently, genetic treatment," said Dr Charo, who is professor of law and bioethics at the University of Wisconsin in Madison and a member of the National Academies' Human Gene Editing Initiative.

Controversy has swirled around CRISPR-Cas9, which acts like "molecular scissors" to fix gene mutations and potentially prevent inheritable diseases.

The first report of human embryo gene editing in the United States was published in August in Nature, as reported by Medscape Medical News. At the time, critics said that this should serve as a wake-up call because it is the first step on the slippery slope toward designer children and the development of a split in humanity between engineered and unengineered classes.

But history doesn't support this view, said Dr Charo, who pointed to the early 1970s, when amniocentesis was becoming common for older pregnant women.

Some Feared Potential of Amniocentesis

At the time, memories of Nazi eugenics programs were still vivid, she pointed out, and children with Down's syndrome were often hidden away or pregnancies were terminated if the test showed Down's.

With the advent of genetic screening, "it was normal for people to think: Are we going to become impatient with imperfection? Are we as parents going to see our children as commodities instead of gifts?" she explained.

But that didn't happen.

This tells me we have not moved to some uniformly eugenic society simply because information is now available.

In fact, amniocentesis led to genetic tests that could be done earlier, more safely, and with a simple blood test.

Even with these advances, some people choose not to use the technology, said Dr Charo. And those who do use it have a wide range of options once armed with the information.

"This tells me we have not moved to some uniformly eugenic society simply because information is now available," she said.

Dr Charo also pointed to preimplantation genetic diagnosis, which came into use in the 1980s and 1990s. That meant that an embryo sitting outside the body, created through in vitro fertilization, could be biopsied and the physician could tell a prospective parent if the embryo had a trait that would result in a devastating disease.

There were calls to prohibit the process because the fear was that "everybody would rush to do in vitro fertilization even if they could conceive naturally, just so they could have the embryo outside the body and have it diagnosed for any number of trivial things," she explained.

But that didn't happen either.

Now gene editing has moved beyond the ability to screen or test; it has the potential to change genes so that diseases such as muscular dystrophy, cancer, and blindness can be averted. And it can go beyond the scope of a single person, Dr Charo added. It has the potential to change the germline and eliminate the gene mutation for future generations, with all the benefits and risks that entails.

There are "countries around the world that have already criminalized germline editing," based only on "fear and speculation," she said.

Dr Charo said she suspects the fear comes partially from people overestimating the role genetics play in human identity.

Overestimating the Role of Genetics

But genes don't tell an athlete whether to play on the men's or women's team in the Olympics, she added. Some people are chromosomally male but their bodies don't respond to testosterone in an ordinary way, so they develop more like a typical female.

And race is not "a genetic phenomenon"; it is a social construct, she said.

"When you look at genetic variation, it's often greater within what we call a racial group than it is between two different racial groups. So genes don't control our racial or ethnic categories," she explained.

Genetic makeup does tell people to whom they are related, but families are not always linked genetically, as evidenced by families made possible by sperm donors or adoption, for instance.

"We see all of these examples in which we recognize that genetics don't tell us everything we need to know," said Dr Charo. "We don't have to assume that having genetic information means we will abuse the choices it facilitates."

"I think in our hearts and our laws, we've come to recognize that genetics is not as determinative of our identity as we might have thought," she said. "And because it has lost some of its power over our identities, it's lost some of its power to cause us to be fearful."

Dr Charo cochaired a committee that examined gene-editing technologies as part of the National Academies' Human Gene Editing Initiative.

TEDMED 2017. Presented November 1, 2017.

Follow Medscape on Twitter @Medscape and Marcia Frellick @mfrellick


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