Speaker 1: Welcome to brain Stuff production of I Heart Radio. Hey
Speaker 1: brain Stuff, Lauren Vogel bomb Here. Mutants are cool, right,
Speaker 1: X men, teenage mutant ninja turtles, and superheroes across comic
Speaker 1: books and films wow us with the special powers that
Speaker 1: have been derived from their genetic mutations. However, these fictional
Speaker 1: genetic mutations are kind of hard to come by. You
Speaker 1: have to have been bitten by a radioactive spider or
Speaker 1: exposed to some weird substance. But what if doing genetic
Speaker 1: modifications wasn't just easy, but fast and cheap too. We're
Speaker 1: a long way from creating superheroes, but a new technology
Speaker 1: called crisper is making editing the genes of life forms
Speaker 1: like crops, livestock, and pests a lot easier. Short for clustered,
Speaker 1: regularly interspaced, short palindromic repeats, a crisper makes it possible
Speaker 1: for us to move genes from any living thing into
Speaker 1: another one, altering DNA for generations to come. It allows
Speaker 1: us to cut away genes that are doing terrible things,
Speaker 1: like those that cause disease, and replace them with segments
Speaker 1: of DNA that are innocuous, Or we could replace innocuous
Speaker 1: segments of DNA with genes that make corn or cattle
Speaker 1: more disease resistant, lessening the need to spray or administer
Speaker 1: antifungals or antibiotics. We might make yeast or algae colonies
Speaker 1: that are really good at producing biofuel that we could
Speaker 1: use to offset our dependence on fossil fuels. While crisper
Speaker 1: technology is pretty awesome, humans genetically modifying different organisms is
Speaker 1: nothing new. On the low tech side. We've been selectively
Speaker 1: breeding crops for a long time. Owen farmers stumbled on
Speaker 1: a particularly juicy orange or brightly colored tomato, they preserved
Speaker 1: those desirable genes by collecting seeds or graphs from that plant.
Speaker 1: But in recent ears, we've kicked biotechnology up a notch.
Speaker 1: In the early two thousands, scientists figured out how to
Speaker 1: use enzymes called zinc finger nucleases to delete and replace
Speaker 1: specific genes in a variety of organisms. These zinc finger enzymes, however,
Speaker 1: were expensive, hard to make, and the success rate was
Speaker 1: not optimal. So while the technology to edit jeanes was there,
Speaker 1: it wasn't until crisper came along that the idea of
Speaker 1: deliberately changing in organism's DNA felt within grasp. The first
Speaker 1: in road toward crisper technology appeared in a journal article
Speaker 1: where scientists reported having found short, repeating segments of DNA
Speaker 1: in equal I bacteria. This type of pattern in bacterial
Speaker 1: DNA is unusual, so they parked up when they noticed
Speaker 1: it and named the phenomenon crisper. Over time, scientists started
Speaker 1: seeing this pattern in many different types of bacteria, but
Speaker 1: there is still no hypothesis for what it was and
Speaker 1: why it was there. But in two thousand five, a
Speaker 1: search in a DNA database showed that the repeating segments
Speaker 1: in bacteria matched DNA from viruses. But why would bacteria
Speaker 1: have harbored away virus DNA? A scientist Eugene Conan hypothesized
Speaker 1: that when bacteria survive a virus attack, they cut up
Speaker 1: the virus into small pieces and store some of the
Speaker 1: virus DNA in their own genome so that they can
Speaker 1: later recognize and attack the virus if they happen to
Speaker 1: meet it again. They're basically storing a picture of the
Speaker 1: virus in their back pocket so that they can recognize
Speaker 1: the bad guy if he ever shows his face again,
Speaker 1: a remarkable defense mechanism of the bacterial immune system. The
Speaker 1: Conan's hypothesis was right. If that virus hits again, the
Speaker 1: bacteria manufacture special assassins. These assassins can read the DNA
Speaker 1: sequence of any virus DNA they run into, recognize it
Speaker 1: if it matches the information they've stored in their DNA,
Speaker 1: and if they do, they'll trap it and chop it up.
Speaker 1: It's as if the bacteria has created very specific, very
Speaker 1: smart scissors. This discovery was pretty cool, but not as
Speaker 1: cool as what University of California Berkeley scientist Jennifer Dowdna
Speaker 1: thought to do with the information. She has since won
Speaker 1: the Nobel Prize in Chemistry along with the Manuel Sharpontier
Speaker 1: for their work on crisper A. Dowdna suggested that scientists
Speaker 1: could use crisper as a tool to help them edit genes.
Speaker 1: If they equipped the bacteria with a segment of DNA
Speaker 1: that is known to be bad, say a gene that
Speaker 1: causes heart failure, they could send the bacteria in to
Speaker 1: seek out the bad gene, where the bacteria would find
Speaker 1: it and clip it out, and then we could take
Speaker 1: advantage of the natural repair mechanism in the bacterial cells
Speaker 1: to throw a more desirable gene in its place. It worked,
Speaker 1: and it kept working. A Crisper has stopped ANSWER cells
Speaker 1: from multiplying, made cells impervious to HIV, helped us create
Speaker 1: disease resistant wheat and rice, and countless other advances in
Speaker 1: Scientists even attempted to use the technology on non viable
Speaker 1: human embryos, but in only a few cases did Crisper
Speaker 1: make the right cuts to the DNA. But this begs
Speaker 1: the question do we even want to use it on embryos?
Speaker 1: Should we be allowed to? Who will regulate the use
Speaker 1: of Crisper. These questions are very much still unsettled, and
Speaker 1: we're still a long ways from using Crisper on growing humans,
Speaker 1: But the scientific community has these and other concerns firmly
Speaker 1: in mind. International ethics panels have convened to discuss the issues,
Speaker 1: and even DOWDNA herself warned against jumping into in womb
Speaker 1: applications for CRISPER anytime soon, given the great risks and
Speaker 1: unknown consequences of editing a human embryos genetic code. For now,
Speaker 1: Crisper is contained mostly to laboratory experiments that are doing
Speaker 1: much less potentially sinister things like attempting to engineer spicy tomatoes.
Speaker 1: A decalf neated coffee beans, and cattle that won't grow horns,
Speaker 1: meaning they won't have to have those horns removed later
Speaker 1: in life as a safety measure. But all of that
Speaker 1: is a matter for another episode. Today's episode is based
Speaker 1: on the article how Crisper Jeane Editing works on how
Speaker 1: stuff works dot com, written by Masa's Salida. Brain stuff
Speaker 1: It's production of iHeart Radio in partnership with how stuff
Speaker 1: Works dot Com and is produced by Tyler Clang. Four
Speaker 1: more podcasts from my heart Radio. Visit the iHeart Radio app,
Speaker 1: Apple Podcasts, or wherever you listen to your favorite shows.