I too have some bad genes that make life pretty challenging at times. This type of tech gives me great hope. I wish I were more qualified to work on it and advance it.
https://en.wikipedia.org/wiki/Gene_therapy_of_the_human_reti... is a good place to start.
https://www.quora.com/How-does-the-CRISPR-Cas9-therapy-manag...
The three major CRISPR companies, Berkeley and Broad are all focused on pushing the technology there. It's not a question of if, it's inevitable. They already know it can be done, the challenge is scaling it up and constantly improving the accuracy and the overall command they have of what eg Cpf1 can do (in the case of Broad & Editas).
A very large percentage of all disease occurs in adults after the age of ~30. That is, well after the person is an adult. Take a look at the disease targets that Editas, Intellia and Crispr Therapeutics are pursuing: they're going after adult diseases long-term, including targeting things such as diseases of the liver more near-term (next five years). Most of their initial targets are focused on easier (relative term) editing targets, the retina being a popular target due to the genes there. First they'll learn to crawl, then walk, then run.
You don't have to edit all the genes in the body to cure most genetic diseases.
It doesn't seem so to me. I've noticed less and less focus on toxicity lately, as if they've given up on that. For example, I took a look at one of the papers[1] from TFA. All they look at is percent of sequences from surviving cells that contained the A->G mutation. They don't report how many cells died during the process to get there.
Also, they see these mutations in the control group too (figure 4 untreated A5 = 99.8), so it seems this may be yet another way to use crispr to select for pre-existing mutants. It's hard to say since no info is provided on the toxicity for this new strategy.
On the other hand, the new strategy may be less toxic since it is only supposed to introduce a single strand break rather than double (ie as opposed to cas9). Reviewers should be on this, not sure why they so consistently drop the ball regarding the role of toxicity in these studies.
[1] https://www.nature.com/nature/journal/vaap/ncurrent/full/nat...
I think my hope is really more into something like the Ray Kurzweil cellular-sized nano computers that can be injected into the body to perform various functions. As we understand what causes certain "bugs" in bodies, perhaps an effective solution can be developed.