OUCH ! I hate to be the 'fear monger' here, but with CRISPR genetic modification, the changes are incorporated into the germ-line of that species, and will be passed down from generation - to - generation. This is the actual plan for the project, and it is being introduced into MAMMALS. Well, humans are also mammals, and similar enough to mice that the mouse line of mammals is very often used as the initial test-bed for medical research targeted at humans. How long will it take this CRISPR modification to jump species-lines, either from virus-aided transfer, or through some form of deliberate weaponization processes?
Damn, I'm kinda' glad that I'm over 70, and hopefully won't be around when (IF) this extinction-level event happens. Granted, it will take multiple generations to spread throughout the global population, but a 'kill-switch' function, or even a more elegant technique involving a basic 'count-down' trigger that self-terminates after a certain number of generation transfers (similar to, and based on, the process of telomere shrinkage with each reproductive cycle), COULD be incorporated into the process in order to limit run-away disasters if the genetic alteration does get loose, or manages to cross species lines.
I shudder to think of the implications of this research being developed to the point that it could target ANY species, and then the inevitable acquisition of the techniques by radicalized, medically-competent , scientists with either deep-pocket private backers, or state-sponsored support.
One geographic transfer / escpe process that pops to mind is a bird, or other long distance traveller, that dumps fecal matter contaminated with this gene-line altering process still active in the biological waste, which then gets eaten by another scavenger (a REALLY HUNGRY individual), and . . . boom - - - the CRISPER agent is suddenly introduced into a population outside of the targeted area, and could very well move from a geo-bound area (like islands) to a wide-open continental arena.
OK, so this is a '. . . sky is falling' scenario, but EVERY precaution needs to be considered - and planned for - when introducing a process that is deliberately designed for total species-line extermination, and there is just no way that ALL escape options will ever be able to be covered with 100% reliability.
Enjoy your nightmares ! ! !