The Case Against CRISPR Babies

A few days after Thanksgiving, a Chinese scientist named He Jiankui shocked the global community by announcing that he had created the world’s first gene-edited, designer babies—twin girls named Lulu and Nana. The two “CRISPR babies” had been born a few weeks earlier to their HIV-positive father Mark and his wife, Grace. Many scientists expressed anger and frustration at the announcement.  U.S. National Institutes of Health Director, Francis Collins, described Jiankui’s work as a “profoundly unfortunate,” “ill-considered,” “unethical,” “scientific misadventure” that “flout[ed] international ethical norms.”

CRISPR is a cutting-edge, molecular editing tool that can be used to alter every gene in any organism, whether it is an elephant, an orchid, or a human infant. If you imagine the human genome—the genetic information found in most of our cells—as an encyclopedia of forty-six volumes with approximately six billion letters, CRISPR gives us the power to change the letter “A” on column two of page 1311 of the third volume of that encyclopedia to a “C.” In theory, we can now edit the genes of any child at will to create designer babies with specific characteristics and desirable traits.

Theory became reality when Jiankui used CRISPR to edit Lulu's and Nana’s genomes. Using standard IVF procedures, he and his team fertilized their mother’s eggs with their father’s sperm and then injected CRISPR into the embryos as soon as they had formed. The research team attempted to edit the twins' CCR5 gene so that it would resemble a variant of the same gene, found among 10 percent of Europeans, that makes a person relatively immune to HIV-AIDS. After testing the embryos to determine if their CCR5 genes had been edited, Jiankui and his colleagues implanted them into Grace’s womb, and she gave birth to the girls in November. Jiankui has argued that he undertook this experiment so that Lulu and Nana would be genetically vaccinated against the HIV virus that had infected their father.

The scientists and ethicists who are critical of Jiankui’s work have three major concerns. First, and most worrisome to me: It is not clear if the Chinese team's CRISPR technology was even safe enough to use with human subjects. At this time, CRISPR is prone to off-target mistakes that alter the genome at random sites other than the intended target gene. Returning to the encyclopedia image, off-target mutations would involve changing a random “C” to a “G” on the wrong page of the wrong volume of the text—a mistake that could increase a patient’s risk for cancer and other life-threatening diseases. Though Jiankui claimed that he and his team found no mistakes in either Lulu’s or Nana’s genomes, they were not able to check every single gene in each of their cells. They failed to adhere to the foundational ethical principle of medicine: Primum non nocere. First, do no harm.

Second, it is not clear that there was a medical need for this particular genetic intervention. Jiankui claimed he wanted to immunize the girls from their father’s HIV. However, there are simpler, cheaper, and less controversial ways of reducing the risk of HIV transmission from father to daughter. Moreover, editing CCR5 reduces, but does not eliminate, the risk of HIV infection. The virus can use another molecular doorway called CXCR4 to enter human cells. In fact, changing the CCR5 gene actually makes a child more susceptible to infection from the West Nile and Japanese encephalitis viruses. Therefore, critics contend that Jiankui took advantage of a vulnerable couple struggling with the stigma of HIV-AIDS to undertake an experiment that had no clear benefit that would outweigh the inherent risks of every genetic intervention.

Finally, critics are concerned that the work of rogue scientists like Jiankui could undermine and delegitimize CRISPR. There are numerous laboratories and biotech companies around the world exploring how CRISPR might ameliorate and even cure many genetic diseases. Just a few days ago, the U.S. Food and Drug Administration approved an application from Editas Medicine in Cambridge, Massachusetts, to begin human clinical trials that use CRISPR to treat Leber Congenital Amaurosis type 10 (LCA10), an inherited disease that leads to vision loss and blindness. The worry is that this high-profile Chinese scandal and others like it could hold back genuine scientific progress like this exciting clinical trial. As Francis Collins put it, “should such epic scientific misadventures proceed, a technology with enormous promise for prevention and treatment of disease will be overshadowed by justifiable public outrage, fear, and disgust.”

These are legitimate ethical concerns. But in my view, they do not address the central moral question raised by CRISPR and other gene editing technologies: Putting aside the moral concerns raised by IVF, which are many, what are the ethical parameters for tinkering with the lifeblood of our children and grandchildren? Should we even be allowed to change the genes of future generations of persons? As I have explained in more detail elsewhere, I think a reasonable case can be made to justify therapeutic interventions that alter the genomes of individuals, both young and old, born and unborn, as long as the genetic surgery is safe and therapeutically beneficial. If it is a great good to heal a child from a genetic disease, then it should also be a great good to prevent him from getting sick in the first place.

However, once the CRISPR technology is deemed safe and effective, it will be difficult for our postmodern and pluralistic society to establish limits for the genetic engineering of our children. I do not believe our commonweal will have the moral courage to tell Manhattan parents, who are willing to pay hundreds of thousands of dollars so that their four-year-old toddlers can attend luxury preschools, that they will not be allowed to spend a meager few thousand dollars to endow those same children with desirable genetic traits thought to be personally and socially advantageous. The advent of designer babies is upon us.

Nicanor Austriaco, O.P., is a professor of biology and of theology at Providence College. 

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