[teh_infallible]

The ethical issue has to do with medical consent. It terrifies me that so many here on HN think it’s ok to experiment on an unborn human being. “Hey, I just gave you cancer before you were born, but hey, it’s all in the name of science, so it’s all good.”

[nightwing]

The decision on risk/benefit can be handled only by parents and doctors, not some bureaucrats or hn commenters who do not know enough about the context. "Hey, you are going to be deaf, because someone decided that 10% increased chance of cancer in 50 years is too serious" is not much better than your example, especially considering that in 50 years cancer will most likely be treatable anyway. (for context https://futurism.com/five-couples-crispr-babies-avoid-deafne...)