WEBVTT - How Does CRISPR Work?

0:00:01.920 --> 0:00:06.480
<v Speaker 1>Welcome to brain Stuff production of I Heart Radio. Hey

0:00:06.559 --> 0:00:11.040
<v Speaker 1>brain Stuff, Lauren Vogel bomb Here. Mutants are cool, right,

0:00:11.760 --> 0:00:15.480
<v Speaker 1>X men, teenage mutant ninja turtles, and superheroes across comic

0:00:15.520 --> 0:00:18.720
<v Speaker 1>books and films wow us with the special powers that

0:00:18.800 --> 0:00:23.280
<v Speaker 1>have been derived from their genetic mutations. However, these fictional

0:00:23.320 --> 0:00:25.960
<v Speaker 1>genetic mutations are kind of hard to come by. You

0:00:26.040 --> 0:00:28.680
<v Speaker 1>have to have been bitten by a radioactive spider or

0:00:28.880 --> 0:00:33.879
<v Speaker 1>exposed to some weird substance. But what if doing genetic

0:00:33.920 --> 0:00:38.720
<v Speaker 1>modifications wasn't just easy, but fast and cheap too. We're

0:00:38.760 --> 0:00:42.440
<v Speaker 1>a long way from creating superheroes, but a new technology

0:00:42.560 --> 0:00:45.960
<v Speaker 1>called crisper is making editing the genes of life forms

0:00:46.000 --> 0:00:52.240
<v Speaker 1>like crops, livestock, and pests a lot easier. Short for clustered,

0:00:52.360 --> 0:00:57.800
<v Speaker 1>regularly interspaced, short palindromic repeats, a crisper makes it possible

0:00:57.880 --> 0:01:01.120
<v Speaker 1>for us to move genes from any living thing into

0:01:01.120 --> 0:01:05.959
<v Speaker 1>another one, altering DNA for generations to come. It allows

0:01:06.040 --> 0:01:09.000
<v Speaker 1>us to cut away genes that are doing terrible things,

0:01:09.040 --> 0:01:12.200
<v Speaker 1>like those that cause disease, and replace them with segments

0:01:12.200 --> 0:01:16.720
<v Speaker 1>of DNA that are innocuous, Or we could replace innocuous

0:01:16.760 --> 0:01:20.240
<v Speaker 1>segments of DNA with genes that make corn or cattle

0:01:20.360 --> 0:01:24.240
<v Speaker 1>more disease resistant, lessening the need to spray or administer

0:01:24.400 --> 0:01:29.200
<v Speaker 1>antifungals or antibiotics. We might make yeast or algae colonies

0:01:29.240 --> 0:01:32.119
<v Speaker 1>that are really good at producing biofuel that we could

0:01:32.240 --> 0:01:36.480
<v Speaker 1>use to offset our dependence on fossil fuels. While crisper

0:01:36.520 --> 0:01:41.640
<v Speaker 1>technology is pretty awesome, humans genetically modifying different organisms is

0:01:41.680 --> 0:01:45.360
<v Speaker 1>nothing new. On the low tech side. We've been selectively

0:01:45.400 --> 0:01:49.080
<v Speaker 1>breeding crops for a long time. Owen farmers stumbled on

0:01:49.120 --> 0:01:53.200
<v Speaker 1>a particularly juicy orange or brightly colored tomato, they preserved

0:01:53.280 --> 0:01:57.720
<v Speaker 1>those desirable genes by collecting seeds or graphs from that plant.

0:01:59.360 --> 0:02:02.560
<v Speaker 1>But in recent ears, we've kicked biotechnology up a notch.

0:02:03.240 --> 0:02:05.760
<v Speaker 1>In the early two thousands, scientists figured out how to

0:02:05.840 --> 0:02:10.240
<v Speaker 1>use enzymes called zinc finger nucleases to delete and replace

0:02:10.400 --> 0:02:15.239
<v Speaker 1>specific genes in a variety of organisms. These zinc finger enzymes, however,

0:02:15.320 --> 0:02:18.640
<v Speaker 1>were expensive, hard to make, and the success rate was

0:02:18.840 --> 0:02:23.960
<v Speaker 1>not optimal. So while the technology to edit jeanes was there,

0:02:24.360 --> 0:02:27.040
<v Speaker 1>it wasn't until crisper came along that the idea of

0:02:27.080 --> 0:02:33.320
<v Speaker 1>deliberately changing in organism's DNA felt within grasp. The first

0:02:33.360 --> 0:02:37.320
<v Speaker 1>in road toward crisper technology appeared in a journal article

0:02:37.480 --> 0:02:41.440
<v Speaker 1>where scientists reported having found short, repeating segments of DNA

0:02:41.800 --> 0:02:45.960
<v Speaker 1>in equal I bacteria. This type of pattern in bacterial

0:02:46.040 --> 0:02:49.040
<v Speaker 1>DNA is unusual, so they parked up when they noticed

0:02:49.080 --> 0:02:54.000
<v Speaker 1>it and named the phenomenon crisper. Over time, scientists started

0:02:54.040 --> 0:02:57.160
<v Speaker 1>seeing this pattern in many different types of bacteria, but

0:02:57.320 --> 0:03:00.040
<v Speaker 1>there is still no hypothesis for what it was and

0:03:00.160 --> 0:03:04.320
<v Speaker 1>why it was there. But in two thousand five, a

0:03:04.400 --> 0:03:07.520
<v Speaker 1>search in a DNA database showed that the repeating segments

0:03:07.520 --> 0:03:13.640
<v Speaker 1>in bacteria matched DNA from viruses. But why would bacteria

0:03:13.720 --> 0:03:18.680
<v Speaker 1>have harbored away virus DNA? A scientist Eugene Conan hypothesized

0:03:18.720 --> 0:03:22.200
<v Speaker 1>that when bacteria survive a virus attack, they cut up

0:03:22.240 --> 0:03:24.799
<v Speaker 1>the virus into small pieces and store some of the

0:03:24.880 --> 0:03:27.560
<v Speaker 1>virus DNA in their own genome so that they can

0:03:27.680 --> 0:03:30.720
<v Speaker 1>later recognize and attack the virus if they happen to

0:03:30.720 --> 0:03:34.000
<v Speaker 1>meet it again. They're basically storing a picture of the

0:03:34.040 --> 0:03:36.520
<v Speaker 1>virus in their back pocket so that they can recognize

0:03:36.560 --> 0:03:38.480
<v Speaker 1>the bad guy if he ever shows his face again,

0:03:38.960 --> 0:03:45.040
<v Speaker 1>a remarkable defense mechanism of the bacterial immune system. The

0:03:45.160 --> 0:03:49.000
<v Speaker 1>Conan's hypothesis was right. If that virus hits again, the

0:03:49.040 --> 0:03:54.360
<v Speaker 1>bacteria manufacture special assassins. These assassins can read the DNA

0:03:54.480 --> 0:03:58.080
<v Speaker 1>sequence of any virus DNA they run into, recognize it

0:03:58.120 --> 0:04:01.000
<v Speaker 1>if it matches the information they've stored in their DNA,

0:04:01.280 --> 0:04:04.080
<v Speaker 1>and if they do, they'll trap it and chop it up.

0:04:04.680 --> 0:04:08.520
<v Speaker 1>It's as if the bacteria has created very specific, very

0:04:08.640 --> 0:04:14.880
<v Speaker 1>smart scissors. This discovery was pretty cool, but not as

0:04:14.920 --> 0:04:18.680
<v Speaker 1>cool as what University of California Berkeley scientist Jennifer Dowdna

0:04:18.800 --> 0:04:21.640
<v Speaker 1>thought to do with the information. She has since won

0:04:21.680 --> 0:04:25.280
<v Speaker 1>the Nobel Prize in Chemistry along with the Manuel Sharpontier

0:04:25.480 --> 0:04:30.240
<v Speaker 1>for their work on crisper A. Dowdna suggested that scientists

0:04:30.240 --> 0:04:33.040
<v Speaker 1>could use crisper as a tool to help them edit genes.

0:04:33.800 --> 0:04:36.520
<v Speaker 1>If they equipped the bacteria with a segment of DNA

0:04:36.600 --> 0:04:39.039
<v Speaker 1>that is known to be bad, say a gene that

0:04:39.080 --> 0:04:42.200
<v Speaker 1>causes heart failure, they could send the bacteria in to

0:04:42.440 --> 0:04:45.479
<v Speaker 1>seek out the bad gene, where the bacteria would find

0:04:45.520 --> 0:04:48.280
<v Speaker 1>it and clip it out, and then we could take

0:04:48.320 --> 0:04:51.480
<v Speaker 1>advantage of the natural repair mechanism in the bacterial cells

0:04:51.720 --> 0:04:56.280
<v Speaker 1>to throw a more desirable gene in its place. It worked,

0:04:56.640 --> 0:05:00.599
<v Speaker 1>and it kept working. A Crisper has stopped ANSWER cells

0:05:00.640 --> 0:05:05.000
<v Speaker 1>from multiplying, made cells impervious to HIV, helped us create

0:05:05.040 --> 0:05:09.960
<v Speaker 1>disease resistant wheat and rice, and countless other advances in

0:05:11.040 --> 0:05:14.560
<v Speaker 1>Scientists even attempted to use the technology on non viable

0:05:14.640 --> 0:05:18.080
<v Speaker 1>human embryos, but in only a few cases did Crisper

0:05:18.200 --> 0:05:22.200
<v Speaker 1>make the right cuts to the DNA. But this begs

0:05:22.200 --> 0:05:25.680
<v Speaker 1>the question do we even want to use it on embryos?

0:05:25.920 --> 0:05:29.120
<v Speaker 1>Should we be allowed to? Who will regulate the use

0:05:29.120 --> 0:05:34.680
<v Speaker 1>of Crisper. These questions are very much still unsettled, and

0:05:34.720 --> 0:05:38.440
<v Speaker 1>we're still a long ways from using Crisper on growing humans,

0:05:39.200 --> 0:05:42.880
<v Speaker 1>But the scientific community has these and other concerns firmly

0:05:42.920 --> 0:05:47.440
<v Speaker 1>in mind. International ethics panels have convened to discuss the issues,

0:05:47.800 --> 0:05:51.040
<v Speaker 1>and even DOWDNA herself warned against jumping into in womb

0:05:51.080 --> 0:05:55.000
<v Speaker 1>applications for CRISPER anytime soon, given the great risks and

0:05:55.080 --> 0:06:01.000
<v Speaker 1>unknown consequences of editing a human embryos genetic code. For now,

0:06:01.120 --> 0:06:05.080
<v Speaker 1>Crisper is contained mostly to laboratory experiments that are doing

0:06:05.320 --> 0:06:10.640
<v Speaker 1>much less potentially sinister things like attempting to engineer spicy tomatoes.

0:06:10.880 --> 0:06:14.520
<v Speaker 1>A decalf neated coffee beans, and cattle that won't grow horns,

0:06:14.720 --> 0:06:17.040
<v Speaker 1>meaning they won't have to have those horns removed later

0:06:17.040 --> 0:06:20.080
<v Speaker 1>in life as a safety measure. But all of that

0:06:20.279 --> 0:06:28.280
<v Speaker 1>is a matter for another episode. Today's episode is based

0:06:28.279 --> 0:06:31.240
<v Speaker 1>on the article how Crisper Jeane Editing works on how

0:06:31.279 --> 0:06:35.000
<v Speaker 1>stuff works dot com, written by Masa's Salida. Brain stuff

0:06:35.040 --> 0:06:37.240
<v Speaker 1>It's production of iHeart Radio in partnership with how stuff

0:06:37.240 --> 0:06:40.000
<v Speaker 1>Works dot Com and is produced by Tyler Clang. Four

0:06:40.040 --> 0:06:43.000
<v Speaker 1>more podcasts from my heart Radio. Visit the iHeart Radio app,

0:06:43.080 --> 0:06:45.800
<v Speaker 1>Apple Podcasts, or wherever you listen to your favorite shows.