Scientists can now edit any gene they want

Biomedical researchers have developed a new technology that allows scientists to edit the genetic code of any species. The CRISPR (Clustered, Regularly Interspersed Short Palindromic Repeats) system allows researchers to destroy, change, or enhance genes. Scientists envision a day when the CRISPR technology will wipe out human diseases caused by abnormalities in a single gene.

On the flip side, the new technology could make the stuff of science-fiction movies a reality. Jennifer Doudna, professor at the University of Berkeley, California, and lead researcher who developed the system, admits that as time goes by and the power of the technology becomes clearer, the frightening possibilities sometimes wake her up at night. “And it is easy enough to use that anybody with basic molecular biology training can use it for genome editing. That’s a bit scary,” Doudna told NPR.

The dilemma is how this technology should be used and when. The CRISPR system could eliminate diseases like sickle-cell anemia. “I don’t think anyone would be against that,” said David Prentice, senior fellow for life sciences at the Family Research Council.

On the other hand, the technology could modify or enhance non-disease traits like IQ or height. It could even be used to add a gene from one species to another to provide capabilities like night vision. Prentice has significant concern about using the technology in the germline—egg, sperm, or early embryo—stage of development because an embryo cannot give informed consent, nor can its future progeny to whom the modification may be passed. There is also the potential for bioterrorism. Gene editing could take a virus that produces the common cold and make it deadly.

Research has exploded at a frenetic pace in the less than two years since Doudna and her colleagues discovered the new technology. Scientists are already using CRISPR to create transgenic animals with genetic material from other species. They use this method to produce animals, usually mice, with the same genetic mutations that cause human diseases. The German Center for Neurodegenerative Diseases in Munich uses CRISPR to make mice that have the gene mutations of Alzheimer’s disease. The center’s Bettina Schmid employs CRISPR to add gene mutations to zebrafish that cause neurodegenerative diseases. “We are absolutely fascinated by the CRISPR/Cas9 system. It allows us to do experiments we only were dreaming about years ago,” Schmid told Alzforum.

Former methods of producing transgenic animals were generally limited to mice.

CRISPR, which works in any species, enables researchers to produce transgenic animals closer in biology to humans. Earlier this year, researchers used it to make transgenic macaque monkeys.

Other possible beneficial applications for CRISPR technology are legion. It could destroy disease-causing bacteria without harming good bacteria. It could also genetically modify organisms, including plants, animals, and microbes, that could serve as living factories for producing drugs, biofuels, biodegradable plastics, or biotechnology applications, the Genetic Literary Project reported.

It will most likely be several years before CRISPR can be tried in humans. Researchers have much more to learn and a few problems to work our first. For example, CRISPR sometimes cuts the wrong gene. Scientists still have limited understanding of how genes interact. Changing one gene may cause problems in another.

The potential for CRISPR to wipe out diseases caused by single gene abnormalities is as exciting as the dangers are frightening, Prentice said: “The $64,000 question is whether we, as a society, will we understand the potential dangers and put limits on the technology instead of trying to correct the damage later. CRISPR technology is not ready for the clinic yet, but it is coming and we need to think ahead.”