Nav: Home

Scientists use 'molecular-Lego' to take CRISPR gene-editing tool to the next level

December 12, 2016

A team of researchers at Western University is playing with molecular-Lego by adding an engineered enzyme to the revolutionary new gene-editing tool, CRISPR/Cas9. Their study, published today in the Proceedings of the National Academy of Sciences (PNAS), shows that their addition makes gene-editing more efficient and potentially more specific in targeting genes.

The scientific community is buzzing with the promise that CRISPR offers for human gene-editing, opening the door to use gene-therapy to treat diseases like cystic fibrosis and leukemia.

In cystic fibrosis, for example, there is one gene mutation which causes the disease in a very large proportion of patients. If it were possible to use CRISPR to cut that mutation out of the genome, the disease could potentially be cured.

"The problem with CRISPR is that it will cut DNA, but then DNA-repair will take that cut and stick it back together," said the study's principal investigator, David Edgell, associate professor at Western's Schulich School of Medicine & Dentistry. "That means it is regenerating the site that the CRISPR is trying to target, creating a futile cycle. The novelty of our addition, is that it stops that regeneration from happening."

The Western researchers have demonstrated that the creation of a new enzyme called TevCas9, which cuts the DNA in two places instead of one, makes it much more difficult for the DNA-repair to regenerate the site of the cut. The researchers created TevCas9 by adding an enzyme called I-Tevl onto the nuclease, Cas9, which is the typical enzyme used to cut DNA in CRISPR.

The study also showed that the addition of Tev shows promise at being much more specific in targeting genes and less likely to cause off-target effects in the genome, which is a significant problem for any potential therapeutic application.

"Because there are two cut-sites, there is less chance that these two sites occur randomly in the genome; much less chance than with just one site," said co-author Caroline Schild-Poulter, associate professor at Schulich Medicine & Dentistry and a scientist at Robarts Research Institute. "This remains to be tested, but this is the hope and the expectation."
-end-
The study resulted from a long-standing collaboration at Schulich Medicine & Dentistry between David Edgell, Caroline Schild-Poulter and Greg Gloor and was funded by the Natural Sciences and Engineering Research Council of Canada (NSERC).

Copies of the embargoed study can be obtained through PNAS on EurekAlert! Journalists can register with EurekAlert at http://www.eurekalert.org/register.php and request access to PNAS materials at http://www.eurekalert.org/account.php

MEDIA CONTACT: Crystal Mackay, Media Relations Officer, Schulich School of Medicine & Dentistry, Western University, t. 519.661.2111 ext. 80387, c. 519.933.5944, crystal.mackay@schulich.uwo.ca@CrystalMackay

ABOUT WESTERN

Western University delivers an academic experience second to none. Since 1878, The Western Experience has combined academic excellence with life-long opportunities for intellectual, social and cultural growth in order to better serve our communities. Our research excellence expands knowledge and drives discovery with real-world application. Western attracts individuals with a broad worldview, seeking to study, influence and lead in the international community.

ABOUT THE SCHULICH SCHOOL OF MEDICINE & DENTISTRY

The Schulich School of Medicine & Dentistry at Western University is one of Canada's preeminent medical and dental schools. Established in 1881, it was one of the founding schools of Western University and is known for being the birthplace of family medicine in Canada. For more than 130 years, the School has demonstrated a commitment to academic excellence and a passion for scientific discovery.

Follow Western Media Relations online:

Website: http://communications.uwo.ca/media/ RSS: http://feeds.feedburner.com/MediaWesternU Twitter: https://twitter.com/mediawesternu

University of Western Ontario

Related Dna Articles:

Penn State DNA ladders: Inexpensive molecular rulers for DNA research
New license-free tools will allow researchers to estimate the size of DNA fragments for a fraction of the cost of currently available methods.
It is easier for a DNA knot...
How can long DNA filaments, which have convoluted and highly knotted structure, manage to pass through the tiny pores of biological systems?
How do metals interact with DNA?
Since a couple of decades, metal-containing drugs have been successfully used to fight against certain types of cancer.
Electrons use DNA like a wire for signaling DNA replication
A Caltech-led study has shown that the electrical wire-like behavior of DNA is involved in the molecule's replication.
Switched-on DNA
DNA, the stuff of life, may very well also pack quite the jolt for engineers trying to advance the development of tiny, low-cost electronic devices.
Researchers are first to see DNA 'blink'
Northwestern University biomedical engineers have developed imaging technology that is the first to see DNA 'blink,' or fluoresce.
Finding our way around DNA
A Salk team developed a tool that maps functional areas of the genome to better understand disease.
A 'strand' of DNA as never before
In a carefully designed polymer, researchers at the Institute of Physical Chemistry of the Polish Academy of Sciences have imprinted a sequence of a single strand of DNA.
Doubling down on DNA
The African clawed frog X. laevis genome contains two full sets of chromosomes from two extinct ancestors.
'Poring over' DNA
Church's team at Harvard's Wyss Institute for Biologically Inspired Engineering and the Harvard Medical School developed a new electronic DNA sequencing platform based on biologically engineered nanopores that could help overcome present limitations.

Related Dna Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Anthropomorphic
Do animals grieve? Do they have language or consciousness? For a long time, scientists resisted the urge to look for human qualities in animals. This hour, TED speakers explore how that is changing. Guests include biological anthropologist Barbara King, dolphin researcher Denise Herzing, primatologist Frans de Waal, and ecologist Carl Safina.
Now Playing: Science for the People

#SB2 2019 Science Birthday Minisode: Mary Golda Ross
Our second annual Science Birthday is here, and this year we celebrate the wonderful Mary Golda Ross, born 9 August 1908. She died in 2008 at age 99, but left a lasting mark on the science of rocketry and space exploration as an early woman in engineering, and one of the first Native Americans in engineering. Join Rachelle and Bethany for this very special birthday minisode celebrating Mary and her achievements. Thanks to our Patreons who make this show possible! Read more about Mary G. Ross: Interview with Mary Ross on Lash Publications International, by Laurel Sheppard Meet Mary Golda...