Imagine a couple screening embryos for a disease gene, and the clinic quietly also selects for height, then hair color, then a "smarter" variant that turns out to have a hidden cancer risk they never anticipated. That's the real problem with editing human embryos: we're making irreversible decisions for someone who has no say, based on today's very incomplete knowledge. We still don't fully understand how genes interact. A single edit can fix one condition while introducing unforeseen problems down the line, affecting not just that child but all their descendants. That's a risk no consent can cover.

If you didn't mean to enter this debate, that's fine, but the question still deserves a real answer. My main worry isn't designer babies, it's the sheer permanence of the mistake. Germline edits don't just affect one embryo; they pass down through every generation. And we know CRISPR can cause off-target mutations we can't always predict. In 2018, He Jiankui edited twins to resist HIV, but we later found the edit may have made them more vulnerable to other diseases. We shouldn't make that bet with someone else's entire genetic future.

Did you know that in one 2020 study, more than half of CRISPR-edited human embryos ended up with large, unintended DNA deletions near the edit site — not fine-tuning, but structural damage? That's the part that scares me. We're not correcting a typo; we're rewriting a book we barely understand, and every copy gets passed down forever. The child can't consent, and neither can their grandchildren. You haven't really made a case for why we should accept that gamble, and I think that's because the risks outweigh any theoretical benefit.