TL;DR
Nearly every gene therapy in people today works like a pair of scissors: it cuts DNA to repair or disable a gene. But many diseases are not caused by a gene that needs cutting out. They are caused by a gene that is not doing enough. A team in Shanghai has now reported a tool that goes the other way, turning a gene up and leaving the DNA uncut, and it is small enough to ride inside the single virus shell that gene therapies normally use to get anywhere. In mice bred to model a severe childhood epilepsy, it raised the activity of the gene they were missing about fourfold, and the animals had fewer seizures and lived longer. In mice carrying a human muscular dystrophy gene, it turned up a backup muscle gene four- to sevenfold, and the animals gripped harder and ran longer for six months. One carrier even turned up several genes at once. This is a mouse study, with no human testing announced and no safety data released. What it offers is a route to the diseases that cutting cannot reach, carried by the same delivery truck the field already knows how to build. For the odds on gene-boosting therapies reaching patients and a timeline of the breakthroughs that would get them there, subscribe.
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