Biochemistry (XI) CRISPR — What is it? Who discovered it? Why does it matter?
Liberal Arts Blog — Wednesday is the Joy of Science, Engineering, and Technology Day
Just another biotech miracle. In this case, the magic tool for cutting and pasting specific genes was invented by bacteria to defend themselves against viruses! You really can’t make this stuff up. The humans who helped figure out how this tool works include Yoshizumi Ishino at Osaka University (1987) and Francisco Mojica at the University of Alicante in Spain (2000). The two scientists generally credited with turning that understanding into usable technology for human use are Jennifer Doudna (University of California, Berkeley) and Emmanuelle Charpentier (Umea University, Sweden) in 2012. But many, many other scientists contributed to the development of this momentous technology. By the way, CRISP is short for Clustered Regularly Interspaced Short Palindromic Repeats. Quotes are from the first link below, a Vox article, “A Simple Guide to CRISPR: One of the Biggest Science Stories of the Decade.” Experts — please chime in. Correct, elaborate, elucidate.
HOW BACTERIA USE GENETIC MUG SHOTS (OR FINGER PRINTS IF YOU PREFER) TO KILL VIRUSES
1. “Whenever a bacterium’s enzymes manage to kill off an invading virus, other little enzymes will come along, scoop up the remains of the virus’s genetic code and cut it into tiny bits. The enzymes then store those fragments in CRISPR spaces in the bacterium’s own genome.”
2. “CRISPR spaces act as a rogue’s gallery for viruses, and bacteria use the genetic information stored in these spaces to fend off future attacks. When a new viral infection occurs, the bacteria produce special attack enzymes, known as Cas9, that carry around those stored bits of viral genetic code like a mug shot.”
3. “When these Cas9 enzymes come across a virus, they see if the virus’s RNA matches what’s in the mug shot. If there’s a match, the Cas9 enzyme starts chopping up the virus’s DNA to neutralize the threat.”
HOW TO MAKE YOUR OWN RNA GUIDED MISSILE — DOUDNA AND CHARPENTIER (2012)
1. “The scientists (Doudna and Charpentier) soon discovered they could “fool” the Cas9 protein by feeding it artificial RNA — a fake mug shot. “
2. “When they did that, the enzyme would search for anything with that same code, not just viruses, and start chopping.”
3. “In a landmark 2012 paper, Doudna, Charpentier, and Martin Jinek showed they could use this CRISPR/Cas9 system to cut up any genome at any place they wanted.”
BASIC UPSIDE POTENTIAL, GENE DRIVES COULD KILL OFF ENTIRE NOXIOUS SPECIES, DOWNSIDE RISKS
1. Upside: more nutritious crops, curing genetic diseases, new antibiotics and anti-virals,
2. Gene Drives: will we be able to wipe out malaria-spreading mosquitos?”Normally, whenever an organism like a fruit fly mates, there’s a 50–50 chance that it will pass on any given gene to its offspring. But using CRISPR, scientists can alter these odds so that there’s a nearly 100 percent chance that a particular gene gets passed on.”
3. Downside: the prospect of designer human babies terrifies many.
A simple guide to CRISPR, one of the biggest science stories of the decade