Yup. That's the idea. The problem right now is the cell entry. The crispr/cas has to be placed in the target cell somehow, and yes, we do this by, e.g. as a replacement of antimicrobials, using phages (viruses that attack bacteria. The mechanism must be specific and effective. Now, sadly, most cells and bacteria come with different phages/viruses that allow cell entry. And so it's a _lot_ of systems that have to be engineered and tested.

Of course, there is also the danger of cutting the genome in a wrong place with similar sequence. Again, this can cause adverse effects like loss of cell function or cancer.

Still, therapy with gene editing mechanisms are already been tested, albeit using the older zinc-fing-nucleases for treatmant of e.g. HIV. These are currently in phase 1/2 testing.

So yes, this is currently an active topic of research. But there are still lots of problems that make this technology only feasible in 10+ years for patiant treatment imo.

A big challenge is that cancer cell genomes are not well conserved. A study was done a while back to look at 1000 breast cancer patients. Mutations were rampant with only a few percentage actually sharing common mutations.

It's already been used in larger animals. http://www.nature.com/nprot/journal/v9/n8/full/nprot.2014.13...

I know there is one paper that describes curing a liver disease (in a mouse I think) using CRISPR-CAS but I can't find the reference right now.

Or, now that we know MS, schizophrenia, and bipolar disorder arise from an activated endogenous retrovirus [1], what say we nip that in the bud.

[1] http://discovermagazine.com/2010/jun/03-the-insanity-virus

Then what if: 100 years later, this virus mutates and starts injecting self-destruct genes everywhere? Might be a good, fast way to a zombie apocalypse!