Aug 242013


In an era of widespread genetic sequencing, the ability to edit and alter an organism’s DNA is a powerful way to explore the information within and how it guides biological function.

A paper from the University of Wisconsin-Madison in the August issue of the journal GENETICS takes genome editing to a new level in fruit flies, demonstrating a remarkable level of fine control and, importantly, the transmission of those engineered genetic changes across generations.

Both features are key for driving the utility and spread of an approach that promises to give researchers new insights into the basic workings of biological systems, including embryonic development, nervous system function, and the understanding of human disease.

“Genome engineering allows you to change gene function in a very targeted way, so you can probe function at a level of detail” that wasn’t previously possible, says Melissa Harrison, an assistant professor of biomolecular chemistry in the UW-Madison School of Medicine and Public Health and one of the three senior authors of the new study.

Disrupting individual genes has long been used as a way to study their roles in biological function and disease. The new approach, based on molecules that drive a type of bacterial immune response, provides a technical advance that allows scientists to readily engineer genetic sequences in very detailed ways, including adding or removing short bits of DNA in chosen locations, introducing specific mutations, adding trackable tags, or changing the sequences that regulate when or where a gene is active.

The approach used in the new study, called the CRISPR RNA/Cas9 system, has developed unusually fast. First reported just one year ago by scientists at the Howard Hughes Medical Institute and University of California, Berkeley, it has already been applied to most traditional biological model systems, including yeast, zebrafish, mice, the nematode C. elegans, and human cells. The Wisconsin paper was the first to describe it in fruit flies and to show that the resulting genetic changes could be passed from one generation to the next.

“There was a need in the community to have a technique that you could use to generate targeted mutations,” says Jill Wildonger, a UW-Madison assistant professor of biochemistry and another senior author of the paper. “The need was there and this was the technical advance that everyone had been waiting for.”

“The reason this has progressed so quickly is that many researchers — us included — were working on other, more complicated, approaches to do exactly the same thing when this came out,” adds genetics assistant professor Kate O’Connor-Giles, the third senior author. “This is invaluable for anyone wanting to study gene function in any organism and it is also likely to be transferable to the clinical realm and gene therapy.”

The CRISPR RNA/Cas9 system directs a DNA-clipping enzyme called Cas9 to snip the DNA at a targeted sequence. This cut then stimulates the cell’s existing DNA repair machinery to fill in the break while integrating the desired genetic tweaks. The process can be tailored to edit down to the level of a single base pair — the rough equivalent of changing a single letter in a document with a word processor.

The broad applicability of the system is aided by a relatively simple design that can be customized through creation of a short RNA sequence to target a specific sequence in the genome to generate the desired changes. Previous genome editing methods have relied on making custom proteins, which is costly and slow.

“This is so readily transferable that it’s highly likely to enable gene knockout and other genome modifications in any organism,” including those that have not previously been used for laboratory work, says O’Connor-Giles. “It’s going to turn non-model organisms into genetic model organisms.”

That ease may also pay off in the clinic. “It can be very difficult and time-consuming to generate models to study all the gene variants associated with human diseases,” says Wildonger. “With this genome editing approach, if we work in collaboration with a clinician to find [clinically relevant] mutations, we can rapidly translate these into a fruit fly model to see what’s happening at the cellular and molecular level.”

Read more . . .


The Latest on: Genome editing
  • In the future we won’t edit genomes—we’ll just print out new ones
    on February 16, 2018 at 11:09 pm

    Instead of engineering or even editing the DNA of an organism ... Jef Boeke leads an effort to create yeast with a man-made genome. NYU School of Medicine “I think this could be bigger than the space revolution or the computer revolution,” says ... […]

  • ‘CAMERA’ records cell action with new CRISPR tricks
    on February 16, 2018 at 9:54 pm

    With the advent of CRISPR, best known as a genome editing tool, many groups have tried to fashion novel recording devices. In a proof-of-concept study published in this week's issue of Science, Harvard University's David Liu and Weixin Tang exploit the ... […]

  • How AI Can Make Editing CRISPR Safer
    on February 16, 2018 at 1:22 pm

    CRISPR is a gene editing tool that consists of two core components. The first cuts the protein whilst the second consists of guide RNA that directs you to the right part of the genome for editing. This guide RNA is 20 letters long, but the sequence of ... […]

  • EXCLUSIVE: Human genome editing raises philosophical questions, Ellen Jorgensen
    on February 16, 2018 at 12:17 pm

    Ellen Jorgensen, Co-Founder of Biotech Without Borders, has said that there isn’t enough connection between the biotech industry and the general public. Speaking to Al Arabiya English on the sidelines of the World Government Summit in Dubai, Jorgensen ... […]

  • Gene editing tool used to detect cancer
    on February 16, 2018 at 7:03 am

    CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) is a recently discovered gene-editing technology that utilizes the bacterial innate immune system to detect specific regions of the genome using an RNA template. The enzyme Cas9 is directed ... […]

  • Genome editor CRISPR’s latest trick? Offering a sharper snapshot of activity inside the cell
    on February 15, 2018 at 12:00 am

    A new cellular recorder that borrows from CRISPR, the revolutionary genome editing tool, now offers what could be a better taping device that captures data on DNA. In Science online this week, chemist David Liu and postdoc Weixin Tang, both of Harvard ... […]

  • New Journal Details Applications, Technology Behind CRISPR Gene Editing
    on February 15, 2018 at 12:00 am

    In another article, Dr. Liu and colleagues detailed results from a spacer-mediated, allele-specific CRISPR/Cas9 genome-editing approach targeting a single-nucleotide mutation in rhodopsin (Rho)-P23H mice, a model of dominant retinitis pigmentosa. […]

  • Genome editing/genome engineering market forecast to 2025 just published
    on February 13, 2018 at 11:22 pm

    This is a professional and in-depth study on the current states of the Genome Editing/Genome Engineering Market Industry. The market is expected to witness a substantial growth internationally due to recent advancements and innovations. - Agency -. […]

  • NCGR and NM-INBRE Host Symposium on Genome Editing
    on February 12, 2018 at 7:38 am

    SANTA FE, N.M., Feb. 12, 2018 /PRNewswire-USNewswire/ -- The New Mexico IDeA Networks of Biomedical Research Excellence (NM-INBRE) and the National Center for Genome Resources (NCGR) announces the 13th annual New Mexico BioInformatics, Science and ... […]

  • Sangamo Therapeutics Presents Initial Safety Data from CHAMPIONS Genome Editing Study for MPS II at WORLDSymposium
    on February 6, 2018 at 4:48 pm

    RICHMOND, Calif., Feb. 6, 2018 /PRNewswire/ -- Sangamo Therapeutics, Inc. (Nasdaq: SGMO) today announced the presentation of initial safety data from the CHAMPIONS Study, the Phase 1/2 clinical trial evaluating SB-913 for the treatment of ... […]

via Google News and Bing News

Other Interesting Posts

Leave a Reply

%d bloggers like this: