Up and down, following the excitement for the latest scientific exploit or frustration for disappointing results. CRISPR is young but already knows how volatile is the market. “Preprint wipes millions off CRISPR companies’ stocks,” cries the March issue of Nature Biotechnology. Continue reading
CRISPR needs to anchor itself near a short sequence called PAM to do its job. In the book “Modern Prometheus” (Cambridge University Press) James Kozubek says a PAM is like a shoehorn, where the Cas9 nuclease begins to clasp down to recognize the right site and cut. In order to fit every gene, a super-adjustable shoehorn would be needed. Think of it as the equivalent of a bump key that can open any door. A Broad Institute group led by David Liu has almost reached the goal with xCas9, the new super-adjustable Cas9 variant described in Nature this week. Continue reading
The first human CRISPR trial approved in the United States is finally recruiting the first patient. In the meantime trials have grown to a dozen in China, considering those revealed by the Wall Street Journal inquiry besides the NIH database (check also this npr article for further details). Over 80 Chinese patients are already receiving a CRISPR-based treatment, while US researchers cautiously plan to test the safety of their experimental therapy on a single subject, and, if everything goes right, two more patients will be treated a month later. Is the West losing its genome-editing edge to Beijing? Continue reading
There is hardly any day without CRISPR news. February starts with researchers correcting abnormalities associated with Duchenne muscular dystrophy (Science Advances) and performing allele-specific editing in blind mice (bioRxiv, forthcoming in The CRISPR Journal). A repechage from January also: how to get pluripotent stem cells by CRISPRing just one gene (Cell Stem Cell).
It’s called evoCas9, and it’s the most accurate CRISPR editing system yet, according to a study just published in Nature Biotechnology. Researchers at the University of Trento, in northern Italy, induced random mutations in vitro on a piece of a bacterial gene coding for the DNA-cutting enzyme (the REC3 domain of SpCas9) and then screened the mutated variants in vivo in yeast colonies by looking at their color. If the molecular scissors work properly, cutting only the right target, the yeast becomes red, but colonies are white if CRISPR cuts off target. Continue reading