This is one of those stories that either is the start of something huge or will sink like a stone: not much in between.

#Tessera's claims are ambitious but not unprecedented. One of our clients does something similar with stem cells, and they have a product that's actually made it to market. As far as I can tell, Tessera is claiming the ability to do this in all kinds of cells, with whole living organisms. Which would be a really big deal.

From a bioinformatics / biostatistics perspective (you knew that was coming) I have Questions about consistency. Doing it once, or ten times, or a thousand, isn't enough. You need to do it *trillions*, very accurately indeed. With cell cultures you just screen out the cells that didn't do what you wanted and keep the ones that did: insert "bury their mistakes" joke here. And with stem cells it's particularly easy to know when you have it right.

"65 percent efficiency—20 times the rate at which it performed unintended or errant edits" sounds quite good on a cell-by-cell basis, although I'd like to see the error bars on those numbers. In a patient, it would be an unmitigated disaster. Congratulations, we've cured your muscular dystrophy ... and given you ten different types of cancer.

More generally, their secrecy does not fill me with confidence, of the 95% variety or any other. As I've said many times before, science done in secret isn't science at all, it's alchemy.

Well. It's early days yet. Let's just hope Tessera isn't another Theranos, because I am *really tired* of that. If they do achieve any of what they're claiming, I'll be cheering them on.

#genetics #geneediting #genewriting #stemcell #bioinformatics #musculardystrophy #cancer

https://www.the-scientist.com/bio-business/can-gene-writing-deliver-what-gene-editing-can-t-70740