TL;DR
Most medicine for inherited disease manages the damage a faulty gene does. Gene editing aims to fix the gene itself, once, inside the body. This week researchers got the first direct look at whether that is actually happening where it counts. A 66-year-old man with alpha-1 antitrypsin deficiency, an inherited disease that clogs the liver and leaves the lungs unprotected, got a single IV infusion of a base editor, a tool that changes one DNA letter without cutting the strand. Ten weeks later a sample of his liver showed the faulty gene corrected in 54% to 57% of its copies, a bit more than half, and the missing protein in his blood rose above the level the report cites as protective. It is one patient in an early trial, and it is the clearest proof yet that the fix lands in the organ, not just in a blood test. For our odds on when a one-dose fix for this disease reaches patients, and the timeline of breakthroughs leading there, subscribe.
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