No, it's not just conservative reservations about fiddling with genetics that makes me annoyed that this line of work is being pushed by some scientists.
Plenty of scientists worry that it is risky to the potential child.
I can't for the life of me understand why people don't see the problem with this: when did the interests of adults who know they have a inheritable major health problem to nonetheless have a child with their own genes start over-riding the obvious moral problem of experimenting in a way that runs a serious risk of creating a child with serious health problems as a result of the experiment?
The moral thing to do, surely, is for that very small part of the population to not insist on propagating their own (or, particularly, the mother's) genes: adopt or use egg donation. With the latter, the mother still gets all the experience of pregnancy, even.