Scientists Have Created 'DNA Scissors' That Can Alter Your Genes, but Should They Use Them?

A spectacular discovery made in 2012 has turned human genome research on its head. Careful what you wish for, comes the warning

The Cas9 complex depicts the Cas9 protein (in light blue), along with its guide RNA (yellow), and target DNA (red).

Source: Bang Wong, from source material provided by Feng Zhang

Biotechnology that can rewrite the genome heralds "a new era of human biology" and raises ethical questions for the medical community, experts in bioethics, and everybody else, according to a group of prominent researchers writing in Science.

The fuss is over "DNA scissors" discovered in microbes in 2012 that can be adapted to edit genetic material, potentially removing disease-enabling mutations and adding in "corrected" DNA strings. Known by its scientific acronym, the CRISPR-Cas9 protein may eventually help realize precision or individualized medicine, the ability to treat or avoid illness such as cancers, muscular dystrophy, and HIV/AIDS by tinkering with the actual genetic coding that makes a person that particular person.

“The simplicity of the CRISPR-Cas9 system allows any researcher with knowledge of molecular biology to modify genomes,” write the 18 scientists, from institutions that include Caltech, Berkeley, Harvard and Stanford. They are led by Nobel-winning biologist David Baltimore of Caltech.

That's a complicated, and potentially dangerous, power. The group recommends that scientists avoid human genome-editing experiments, even where they're legal, and that research and funding sources be transparent. This is the second call to arms in two weeks. An essay last week in Nature called for a moratorium on experiments on human embryos, eggs, or sperm.

Genome engineering has become so powerful that civic leaders and the general public should be brought into the debate, the scientists say. What happens if CRISPR snips out the wrong DNA, or adds in a sequence in the wrong place? If these techniques are ever deemed safe and effective, who would qualify for treatment, and when? The mind reels. When's the next remake of The Fly? Don't it make my brown eyes blue?

A revolution in basic research is already under way. Labs around the world have demonstrated the potency of CRISPR. Scientists at Virginia Tech put out a study on Monday that shows how gene editing in mosquitoes may lead to novel strategies to fight the spread of malaria. New approaches to attacking HIV may come from snipping the virus out of human cells, according to Salk Institute research published this month. Korean researchers in February made news by testing the technique on human cells. The Center for Genome Engineering at Seoul's Institute for Basic Science boasts: "The whole genome is under our control." 

Is it? Scientists involved in the discovery have founded competing start-ups to commercialize what's considered the most revolutionary bioengineering technology since the advent of recombinant DNA in the 1970s, MIT's Technology Review reported in December.

The questions surrounding CRISPR-Cas9 are emblematic of a cultural shift in the very meaning of the human body. Consider this novelty story from last week. In 1962, Winston Churchill was hospitalized for a broken hip. After his release, a student nurse at the hospital got permission to take a vial of his blood home as a memento, instead of destroying it. Before she died, she gave it to a friend, who put it up for auction this year to mark the 50th anniversary of Churchill's death. The auction house pulled the item from its catalog before its scheduled March 12 sale, at the request of Churchill’s heirs. 

No part of that story is OK, from the initial taking of someone’s blood without his knowledge to its proposed sale with public fanfare. New York Presbyterian Medical Center, where former president Bill Clinton had heart surgery in 2010, didn't return a call about procedures in place that prevent such episodes today. Can't blame them. It's a ridiculous question, or should be.

And maybe today it's an unnecessary one. Biological and medical technologies have evolved, and ethics, slowly, with them. Legal and professional institutions treat human blood and tissue as personal information that belongs to an individual, not potential souvenirs.

The revolution in thinking about the human body is only getting started. The remains of saints used to be kept and venerated for generations, said Ross McKinney, director of the Trent Center for Bioethics at Duke University. "There was a rich history of hanging on to bits of famous people and imparting to it miraculous properties," he said. "More recently we'd be more concerned about the possibility that somebody can go chasing after genetic information that really gets into the privacy of the heirs and relatives of the individual."

Ever since scientists developed powerful genome sequencers, DNA has been “readable” in a way that’s analogous to books, credit cards, or email. Code is just code: If there's any information in a string of characters—whether it's rendered in a binary, alphabetical, or genetic code—we can crack it. 

It's a common enough notion in computing. As computers became more powerful in the '90s and '00s, the "read-only memory" of CD-ROMs morphed into storage disks capable of "read-write memory." CRISPR-Cas9 makes the comparison as real as ever. The genetic code is the software that runs living things, and just as with digital technology, DNA is being upgraded, from a read-only to a read-write medium. 

    Before it's here, it's on the Bloomberg Terminal. LEARN MORE