Some of the biggest discoveries in science often hide away in plain sight for many years before their importance is fully realised. This is certainly true of Crispr (pronounced crisper), which has taken the world of genetics by storm.
Crispr stands for clustered regularly interspaced short palindromic repeats, a devilishly contrived acronym which just about sums up why it was ignored for so long. For nearly two decades after Japanese researchers first discovered Crispr in bacteria in 1987, scientists mostly dismissed it as junk DNA.
In fact, the apparently nonsensical sequences within Crispr, which were repeated in palindromic order (the same backwards as forwards), did have a purpose and were far from junk. About six years ago, scientists discovered that these DNA sequences matched the genetic sequences of various viruses that attack bacteria, which led to the discovery of a sophisticated bacterial immune system.
Far from being junk, Crispr was actually a way of storing the genetic information of an invading virus in the form of a palindromic DNA sequence. The bacteria used this genetic memory to target the viral invader by chopping it up with powerful Crispr-associated (CAS) enzymes capable of cleaving its DNA molecule, just like a pair of molecular scissors.
The mystery of Crispr was finally resolved by Jennifer Doudna of the University of California, Berkeley, a specialist in RNA, the smaller molecular cousin of DNA. About seven years ago, she was asked by a university colleague to look into this genetic peculiarity of bacteria and quickly became fascinated.
The more we looked into it, the more it seemed extremely interesting, Professor Doudna said. Then, in 2011, she met Emmanuelle Charpentier of Umea University in Sweden at a scientific conference. Professor Charpentier told Professor Doudna of another kind of Crispr system that seemed to rely on a single gene, now called CAS9.
Both professors collaborated on the project and in August last year published what is now considered the seminal paper showing that CAS9 was an enzyme capable of cutting both strands of a DNA double helix at precisely the point dictated by a programmable RNA sequence in other words, an RNA molecule that could be made to order. We found that CAS9 has the ability to make a double-stranded break in DNA at sites that are programmed by a small RNA molecule. What was so important was that we could really show how the CAS9 protein worked, Professor Doudna said.
Not only were we able to work out how it worked, we were able to reprogramme it to recognise new DNA sequences. If it could be made to work in eukaryote systems plants and animals then youd have a system where you could effectively decide where to produce a double-stranded break in that cells genome.
It not only worked on plants and animals, it worked beautifully. Professors Doudna and Charpentier had found the holy grail of genetic engineering a method of cutting and stitching DNA accurately and simply anywhere in a complex genome. Until now, this was carried out by modified viruses, which inserted their DNA at random, or by elaborately cumbersome techniques known as zinc fingers or Talens.
You can actually introduce new genetic information at the site of cleavage. So it has become a powerful way of doing genetic engineering. Its a fundamentally different way of recognising DNA target sites, Professor Doudna said.
Here is the original post:
Biochemist Jennifer Doudna hailed for discovery of ‘holy grail’ of genetic engineering
- Main Show Only - Genetic Engineering - Coast to Coast AM - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- RTPB | Genetic Engineering [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- Stop Monsanto From Poisoning Hawai'i: Genetic Engineering Chemical Warfare - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- Informatics 161 PSA: Human Genetic Engineering - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- Don't Trust Whole Foods or Other Health Food Stores For Non- GMO Foods | Genetic Engineering - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- Genetic Engineering - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- Easier Genetic Engineering! (Brainstorm Ep69) - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- TEDxUCIrvine - Francisco Ayala - Cloning, Genetic Engineering, [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- Genetic Engineering in Agriculture - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- Infowars Special Report : Genetic Engineering - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- Glowing Rats and Extreme Genetic Engineering - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- Endangered Cat Born at Audubon - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- Danger of Genetic Engineering - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- AQA GCSE core science and B1 - Genetic Engineering - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- genetic engineering rDNA.wmv - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- Genetic Engineering for Human Enhancement.mp4 - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- Genetic Engineering - Seven Wonders of the Microbe World (6/7) - Video [Last Updated On: September 7th, 2012] [Originally Added On: September 7th, 2012]
- Promising new drug target for inflammatory lung diseases [Last Updated On: September 8th, 2012] [Originally Added On: September 8th, 2012]
- Mandatory GM Labeling Would Require Major Change [Last Updated On: September 10th, 2012] [Originally Added On: September 10th, 2012]
- GEN reports on ocular therapeutics targeting the retina [Last Updated On: September 11th, 2012] [Originally Added On: September 11th, 2012]
- Prop. 37: Another example of the perils of the initiative process [Last Updated On: September 15th, 2012] [Originally Added On: September 15th, 2012]
- Genetic test predicts risk for Autism [Last Updated On: September 19th, 2012] [Originally Added On: September 19th, 2012]
- Immediate withdrawal of unsafe GE corn vital - Greens [Last Updated On: September 20th, 2012] [Originally Added On: September 20th, 2012]
- Immediate withdrawal of unsafe GE corn vital [Last Updated On: September 20th, 2012] [Originally Added On: September 20th, 2012]
- NZ out of step on GE [Last Updated On: September 21st, 2012] [Originally Added On: September 21st, 2012]
- Ballot Watch: Labeling genetically engineered foods [Last Updated On: September 30th, 2012] [Originally Added On: September 30th, 2012]
- Just another GE mirage [Last Updated On: October 2nd, 2012] [Originally Added On: October 2nd, 2012]
- The GM Barnyard [Last Updated On: October 3rd, 2012] [Originally Added On: October 3rd, 2012]
- Free Engine [Last Updated On: October 3rd, 2012] [Originally Added On: October 3rd, 2012]
- Cellectis Publishes Results Paving the Way for New Therapeutic Approaches against Cancer and Genetic Diseases [Last Updated On: October 3rd, 2012] [Originally Added On: October 3rd, 2012]
- Does moral decision-making in video games mirror the real world? [Last Updated On: October 3rd, 2012] [Originally Added On: October 3rd, 2012]
- Animals engineered with pinpoint accuracy [Last Updated On: October 3rd, 2012] [Originally Added On: October 3rd, 2012]
- Valley farmers fear 'modified' wording in Prop. 37 [Last Updated On: October 4th, 2012] [Originally Added On: October 4th, 2012]
- No on Proposition 37 [Last Updated On: October 4th, 2012] [Originally Added On: October 4th, 2012]
- The Dangers of Genetic Engineering [Last Updated On: October 5th, 2012] [Originally Added On: October 5th, 2012]
- Are inhaled medications effective and safe in critically ill patients on mechanical ventilation? [Last Updated On: October 5th, 2012] [Originally Added On: October 5th, 2012]
- Calif. initiative will test appetite for GMO food [Last Updated On: October 7th, 2012] [Originally Added On: October 7th, 2012]
- Calif. initiative will test appetite for GMO food - Sat, 06 Oct 2012 PST [Last Updated On: October 7th, 2012] [Originally Added On: October 7th, 2012]
- California to vote on 'genetically modified' labels [Last Updated On: October 7th, 2012] [Originally Added On: October 7th, 2012]
- California initiative will test appetite for genetically modified foods [Last Updated On: October 7th, 2012] [Originally Added On: October 7th, 2012]
- Do we have an appetite for genetically modified food? [Last Updated On: October 7th, 2012] [Originally Added On: October 7th, 2012]
- Genetic labelling mooted in California [Last Updated On: October 7th, 2012] [Originally Added On: October 7th, 2012]
- California initiative to test appetite for 'genetically engineered' food [Last Updated On: October 7th, 2012] [Originally Added On: October 7th, 2012]
- New tool for making genetic engineering of microbial circuits reliably predictable [Last Updated On: October 10th, 2012] [Originally Added On: October 10th, 2012]
- Researchers develop new tool for making genetic engineering of microbial circuits reliably predictable [Last Updated On: October 10th, 2012] [Originally Added On: October 10th, 2012]
- A Welcome Predictability [Last Updated On: October 10th, 2012] [Originally Added On: October 10th, 2012]
- Engineered flies spill secret of seizures [Last Updated On: October 12th, 2012] [Originally Added On: October 12th, 2012]
- Genetic 'remix' key to evolution of bee behavior, researchers find [Last Updated On: October 15th, 2012] [Originally Added On: October 15th, 2012]
- Can vaccines be delivered via the lungs instead of by injection? [Last Updated On: October 15th, 2012] [Originally Added On: October 15th, 2012]
- Food labeling regulations [Last Updated On: October 16th, 2012] [Originally Added On: October 16th, 2012]
- Research and Markets: Therapeutic Antibody Engineering: Current and Future Advances Driving the Strongest Growth Area ... [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- Is there a difference between GE & GMO? [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- Port Townsend Food Coop: A Sad Story of GMO Crop Cross Pollination - Video [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- PUT IT IN YOUR MOUTH! Yes to Prop 37 — it's your right to know what's in your food! - Video [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- editta braun company: planet LUVOS (clip, 4:30) - Video [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- Mimic: The Director's Cut (Blu-ray Trailer) - Video [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- South Park Season 1 Episode 7 - An Elephant Makes Love to a Pig - Video [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- Yes on Prop 37: Animated Video - Video [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- The Day of the Triffids Part 1 Full Movie - Video [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- YES on prop 37 "flashmob" march - Santa Cruz, CA Sept. 2012 - Video [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- World's Weirdest Places Discussed - Video [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- THE CLUB OF ROME - DEPOPULATION AGENDA 21 - THE UNHIVED MIND - Video [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- 27-Medical BiotechnologySG Part II.Gene Therapy, Tissue Engineering and Nanotechnology.mov - Video [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- 26-Medical BiotechnologySG Part Ic. Animal and Human Cloning and Genetic Engineering.mov - Video [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- How to Clone Animals - Video [Last Updated On: November 2nd, 2012] [Originally Added On: November 2nd, 2012]
- Fringe Opening sequence (Season 3 - The Day We Died) - Video [Last Updated On: November 4th, 2012] [Originally Added On: November 4th, 2012]
- Fringe Opening sequence (Season 3 - Olivia) - Video [Last Updated On: November 4th, 2012] [Originally Added On: November 4th, 2012]
- Fringe Opening sequence (Season 3 - Entrada) - Video [Last Updated On: November 4th, 2012] [Originally Added On: November 4th, 2012]
- Fringe Opening sequence (Season 4) - Video [Last Updated On: November 4th, 2012] [Originally Added On: November 4th, 2012]
- Fringe Opening sequence (Season 3) - Video [Last Updated On: November 4th, 2012] [Originally Added On: November 4th, 2012]
- Fringe Opening sequence (Season 2) - Video [Last Updated On: November 4th, 2012] [Originally Added On: November 4th, 2012]
- Fringe Opening sequence (1985) - Video [Last Updated On: November 4th, 2012] [Originally Added On: November 4th, 2012]
- Dendritic Cells: Biology And Clinical Applications - Video [Last Updated On: November 4th, 2012] [Originally Added On: November 4th, 2012]
- Port Townsend Food Coop: "I want my food untainted by GMOs" - Video [Last Updated On: November 4th, 2012] [Originally Added On: November 4th, 2012]
- Catholic Priest vs. Biologist - Video [Last Updated On: November 4th, 2012] [Originally Added On: November 4th, 2012]
- Watch Real Life Superhero Muscles Like Marvel's The Avengers - Video [Last Updated On: November 4th, 2012] [Originally Added On: November 4th, 2012]
- Fringe Opening sequence (Season 1) - Video [Last Updated On: November 4th, 2012] [Originally Added On: November 4th, 2012]
- Fringe Opening sequence (The Final Season: "Fight For The Future") - Video [Last Updated On: November 4th, 2012] [Originally Added On: November 4th, 2012]
- Port Townsend Food Coop: I Want To Know If GMOs Are In My Food - Video [Last Updated On: November 4th, 2012] [Originally Added On: November 4th, 2012]
- ProCognia jumps on expanded biosimilar collaboration [Last Updated On: November 7th, 2012] [Originally Added On: November 7th, 2012]