This shouldn't be legal. If people fuck themselves up the worst case isn't just them dying, they can accidently unleash a virus. Pretty unlikely, but just the smallest possibility is still too much when the outcome can be so bad. It's not unreasonable that tinkering with dna will unleash some dormant retrovirus.
What does seem likely is that they give both themselves and their germ line a genetic mutation. Editing yourself and then having children would be incredibly irresponsible. If you affect your germ cells, you're not just editing yourself, but all of your descendants.