TL;DR
Some cases of ALS, the disease that slowly takes away the ability to move, speak and breathe, start with a single stretch of DNA that repeats far too many times in a gene called C9ORF72. A Toronto company, Specific Biologics, says it has built a gene editor that cuts on both sides of that overgrown stretch and snips it out, leaving the healthy part of the gene intact, and that in cells taken from patients the repeat expansion collapsed almost completely. Those are company claims, with no data or paper published alongside them. The company just raised $35 million to take the editor into a first trial in people, and it says the same two-cut trick could in principle be aimed at more than 40 repeat-expansion diseases, a list that includes Huntington's disease and fragile X. To see our odds on when a person with ALS actually gets this editor, and the timeline of breakthroughs that leads there, subscribe.
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