Future Tense

CRISPR, Explained

Don’t know a genetically modified organism from modified corn starch? Still not sure if this CRISPR thing is for storing vegetables or for altering them? You better study up before the Jennifer Lopez–produced TV show C.R.I.S.P.R. debuts. Luckily, the Royal Society has this five minute animated video primer on gene editing to get you up to speed, beginning with the essential basics: DNA, what genes are, and how organisms inherit genes and express traits.

Of course, humanity’s efforts at altering and exploiting genetic traits started not in the test tube era, but in the ancient past, as our forgotten ancestors first began to selectively breed plants and animals to obtain desired traits. In the video, the Dwarf apple tree is shown as the genetic basis for the Ribston pippin apple in the early 18th century, and then in the early 19th century the Cox’s orange pippin apple—one of the most beloved English apples.

But the gene editing tools available to biochemists today are far faster and more accurate than the methods of plant and animal husbandry. The CRISPR gene editing technique, for instance, allows scientists to pinpoint an exact sequence of DNA within a gene, excise it using the Cas9 enzyme, and paste in a new segment of DNA in place of the original. As the video suggests, this is a “find and replace for the genetic instruction manual.”

The consequences of this technology could be huge, as could the benefits and the hazards. Gene editing could one day be used to treat all kinds of disease—from cancer to Huntington’s disease. In 2015, the video notes, researchers sent a 1-year-old girl’s leukemia into remission with gene editing therapies, and malaria, a killer since the time of the dinosaurs, could one day be eradicated by editing the mosquito genome.

Among the downsides are designer babies and designer pets, though whether those are truly downsides depends on one’s aesthetic and ethical points of view. More concerning would be the use of gene editing to create and weaponize more deadly diseases.

Given humanity’s long history of genetically modifying plants and animals, as well as a fast approaching future where we may begin altering ourselves, there are a lot of decisions to be made—both at the societal and personal level. It’s important to be well-informed, and this video is a great start.