
A paper published in Nature Biotechnology by Allan Bradley and colleagues from the Wellcome Sanger Institute in Hinxton, UK, shows that classical CRISPR editing can cause large rearrangements of DNA near the target site in actively dividing cells. We may think of it as the latest CRISPR alarm, but also as a demonstration of how biomedical research works. Firstly: no technology is perfect, but the best ones are perfectible. CRISPR belongs to this category because it is an extraordinarily versatile and fast-evolving biotech platform. When reading news like “CRISPR causes this or that problem,” the first question to ask is: which CRISPR variant are we talking about? Continue reading


Faster, better, cheaper is a motto adopted by Nasa that perfectly fits CRISPR as well. The most popular technique for genetic modification, in fact, has the reputation of being quick, affordable and precise. This deserved good name was unexpectedly tarnished by a study questioning the technology precision, published in the June issue of Nature Methods. However, reports about CRISPR’s demise have been greatly exaggerated, to paraphrase Mark Twain. Just over a month later, three analyses challenging the controversial study are already available in the pre-publication archive bioRxiv, and Nature Methods has alerted its readers about the criticisms received by publishing an
Perfection is not of this world, and no technology is perfect. But tolling the bell for CRISPR because of a single preliminary study last week was premature at best. Many voices are doubting the meaning of the Nature Methods paper reporting “hundreds of unintended mutations” putatively caused by genome editing. Some researchers have already announced that critical analyses and rebuttals are forthcoming.