Powerful CRISPR upgrade uses 'jumping genes' to directly insert DNA
"and some additional from my notes/tally of sources I meant to include:"
Health 6 June 2019
Transposase enzymes can insert new pieces of DNA in a genome LAGUNA DESIGN/SCIENCE PHOTO LIBRARY
By Michael Le Page
The CRISPR genome editing technology currently revolutionising biology may soon become even powerful. A new variant of the method based on “jumping genes” could make it much easier to insert pieces of DNA into genomes.
The standard form of CRISPR involves adding a protein called Cas9 to a cell along with a piece of guide RNA. The protein searches through the genome until it finds DNA .. https://www.newscientist.com/term/dna/ .. that matches the guide RNA sequence and then cuts the DNA at this point. Some DNA is lost when the cell sticks the ends back together, resulting in deletions that typically disable genes.
But in many cases it would be better to fix faulty genes rather than disable them. It is possible to do this by adding a corrected gene to a cell along with the CRISPR Cas9 protein and the RNA guide. Cells sometimes splice the corrected version into the genome when they repair the DNA.
Unfortunately, this typically works only 20 per cent of the time, and in many cell types it simply doesn’t work at all.
Lots of teams are working on improving the “find and replace ” function .. .. https://doi.org/10.1038/s10038-017-0352-4 . Feng Zhang of the Massachusetts Institute of Technology has now developed a whole new approach based on transposons, also known as jumping genes.
It was recently discovered that a few jumping genes have hijacked the CRISPR systems .. https://doi.org/10.1073/pnas.1709035114 .. that bacteria use to defend against viruses. These Tn-7 jumping genes use a protein called Cas12k to find specific sequences. But these variants don’t cut the DNA at the target sequence; instead transposase enzymes insert the jumping genes into this site.
Feng’s team have now shown the Cas12k protein and the Tn-7 transposes can be used to insert pieces of DNA several thousand letters long into specific sites in the genome of the E. coli bacterium. What’s more, it worked around 80 per cent of the time.
“Overall, the results shown in the paper are remarkable,” says Gaeten Burgio of the Australian National University, who studies CRISPR systems. But the team have yet to show this approach works in animal and plant cells, he cautions.
This is all such intriguing science, which affords a new, and expanded, meaning to the phrase "little things mean a lot."
Thia post is specifically posted to the fifth down ..
Kazuo Ishiguro: 'We’re coming close to the point where we can create people who are superior to others' - tie in particular to http://investorshub.advfn.com/boards/read_msg.aspx?message_id=126997323 Social changes unleashed by new technologies could undermine core human values unless we engage with science, warns author Imagine a two-tiered society with elite citizens, genetically engineered to be smarter, healthier and to live longer, and an underclass of biologically run-of-the-mill humans. It sounds like the plot of a dystopian novel, but the world could be sleepwalking towards this scenario, according to one of Britain’s most celebrated writers. Kazuo Ishiguro argues that the social changes unleashed by gene editing technologies, such as Crispr, could undermine core human values. “We’re going into a territory where a lot of the ways in which we have organised our societies will suddenly look a bit redundant,” he said. “In liberal democracies, we have this idea that human beings are basically equal in some very fundamental way. We’re coming close to the point where we can, objectively in some sense, create people who are superior to others.” [...] https://www.theguardian.com/science/2016/dec/02/kazuo-ishiguro-were-coming-close-to-the-point-where-we-can-create-people-who-are-superior-to-others
What does the future hold? Our grandchildren will most certainly experience more.