John Oliver Explains

John Oliver tackles gene editing, biohackers, and wolf-related hazards on Last Week Tonight

If you don't quite understand what gene editing is, or you watched the Rock's latest movie and think we're just a few lab accidents away from 30-foot wolves taking over the planet, John Oliver is here to help.

Gene editing is often talked about with both excitement and alarm, Oliver said on Sunday's Last Week Tonight. Many think it's "either going to kill all disease or kill every last one of us," but gene editing has actually been in existence for awhile. The latest technology is CRISPR, which is like copying and pasting in a Word document, Oliver explains; theoretically, scientists can find something they want to change on a strand of DNA, cut it out, and paste in a fix. The potential is "huge," he said, with scientists being able to possibly use CRISPR to eradicate cystic fibrosis or sickle cell anemia, but gene editing is also "wildly difficult," as many diseases have multiple genes that contribute to them.

CRISPR's underlying technology is relatively inexpensive, and there are biohackers who fork over a few hundred dollars for their own kits, frustrating scientists who worry that one accident by a biohacker will set the whole field back. Oliver used two examples to show the different approaches to gene editing — a biohacker named Josiah Zayner who injected himself with DNA modified using CRISPR in order to get larger muscles (it didn't work, Oliver noted) and a scientist named Kevin Esvelt who wants to introduce mice to Nantucket that have been genetically edited so they cannot pass Lyme disease to ticks. He will be extremely careful, but is worried because there's no way he can completely control all aspects of the study.

Ecosystems are extremely delicate, and one wrong move can completely mess things up. What's worrying to Oliver is people who aren't concerned about the consequences, as well as those who believe certain medical conditions are flaws and feel the need to "fix" people who don't think they have a problem. "Balancing risk and potential rewards is going to be tricky," Oliver said. Watch the video — which has some coarse language and images of fake mice and ticks that might scar you for life — below. Catherine Garcia