This is gene editing on a large scale, but they suggest that they're "permanently changing someone's DNA", which is true, and it's false. It's pretty inaccurate

This is gene editing on a large scale, but they suggest that they're "permanently changing someone's DNA", which is true, and it's false. It's pretty inaccurate. The issue with Hunter's syndrome is that the body refuses to produce a set of enzymes that break down certain sugars, resulting in a buildup, resulting in complications, resulting in death. In order to fix it, they're going to use a virus that inserts a new gene that produces the breakdown enzymes in a large number of cells, up to hundreds of thousands. Large numbers however only in absolute terms. If compared with how much cells they have we're talking one in a million or even less cells of their body. Because this will cause those cells to produce those breakdown enzymes, which will then spread through the body and do the work, this should work to treat the disease. But there's a lot of caveats: They're introducing a new gene indiscriminately. They're not fixing the existing gene. Also they're only "converting" a relatively tiny amount of cells. Enough so the treatment sticks (ie. it needs to infect stem cells), but certainly not all. Even so, it is expected the effects of the treatment will grind down over time, maybe requiring regular treatments, at an unknown rate. Procreation cells, in both men and women, are protected against viruses through special mechanisms. The virus will not be effective on them, and therefore their children will at least be carriers of the disease and potentially need treatment themselves. The sad thing is what these treatments will lead to over the long term. If we treat many people for metabolic diseases, genetic diseases will "spread". The diseases are currently limited from spreading because they are at an evolutionary disadvantage: infected people die before having kids. If that's fixed, there will be increased rates of genetic defects in children. Eventually this may lead to very few human babies being born without metabolic disease and nearly everyone being dependent for their life on treatments like these. Of course, that's a long term potential consequence. It would not be moral to not treat these people. And of course, in the future it may be possible to target procreation cells as well, and we probably should.