Circumcision is absolutely mutilation.
> Genetic tampering can lead to all kinds of unknowable nightmares.
You can "tamper with your kid's DNA" just by having kids with the wrong person and passing down a genetic disease.
There are plenty of unknowable things about life. You could die in a car crash. You certainly will die eventually.
Should we avoid taking risks entirely because they might result in bad outcomes? With this mindset, humanity would have never progressed. We would have never left our caves if we were paralyzed by our own fear.
Humanity is still early stage. We are not so different from those that once ventured out of their caves. To them, we owe everything. It is a disservice to all future humans that will ever live if we stop taking trajectory-changing bets because things could go wrong.