How CRISPR Gene Editing Works

The GMO Backstory

While the CRISPR technology is pretty awesome, humans genetically modifying different organisms is nothing new. On the low-tech side, we have been selectively breeding crops for a long time. When farmers stumbled upon a juicy orange or a brightly colored tomato, they preserved those desirable genes by planting seeds from that plant.

But in recent years, we've kicked biotechnology up a notch. In the early 2000s, scientists figured out how to use enzymes, called zinc finger nucleases, to delete and replace specific undesired genes in a variety of organisms. The zinc finger enzymes, however, were expensive (upward of $5,000 a pop), hard to make, and the success rate was not optimal [source: Ledford].

So while the technology to edit genes was there, it wasn't until CRISPR came along that the idea of deliberately changing an organism's DNA felt within grasp. The first reference to CRISPR was in a 1987 journal article where scientists reported finding the short repeats of DNA that are the basis of the technology in E. coli bacteria. But it wasn't until 2012 that CRISPR became relevant. Since then, the use of CRISPR has skyrocketed in the scientific community. More than a billion dollars have been raised as startup capital for biotechnology companies that are using the technique [source: Ledford]. Government funding for CRISPR research is also through the roof.

In 2014 alone, close to $90 million was committed by the National Institutes of Health for CRISPR research [source: Ledford]. And since 2010, over 200 patents related to CRISPR have been filed [source: Ledford]. The rapid pace of research does not seem to be slowing down. As scientists learn more about CRISPR, it seems they are learning less about how the technique is limited and instead about how powerful it is. Thus far (2016), there is no organism it doesn't work on (CRISPR has been used successfully on human cells, but not yet in viable human embryos). So the technology is possibly universal. And just as important, it's very cheap. It generally costs about $75 to employ the technique, and can be as cheap as $30 [sources: Radiolab, Ledford].

So what is it about this technique that makes it so powerful?