A 2017 study on CRISPR-edited human embryos found that most ended up as mosaics — meaning only some cells got the edit while others didn't. We think we're drawing a clear line on the map of human genetics, but the pen is skipping, and that map gets copied into every cell of a future person's body. Once that imperfect line is passed down through generations, you can't erase it. The downside isn't hypothetical; it's a permanent, irreversible bet made on a shot we can't fully control.

The other side's opening remark doesn't really map to this debate, but let me push on the science anyway. Here's the thing: a 2016 study using CRISPR on embryos found that the repaired DNA often came from the sperm's own gene, meaning the edit was borrowed, not written cleanly. Think of editing as building a bridge over a canyon—you lay the girder, but the bedrock shifts. Germline edits don't just affect one person; they create a highway that every descendent must travel, with no toll booth to turn back. If we can't guarantee the foundation, we shouldn't pave the road.

If you're just here to poke at the debate, that's fine, but imagine the editing itself being that careless. A scientist tweaks a single embryo to remove a disease gene, yet the embryo ends up a patchwork of edited and unedited cells. That embryo becomes a person walking around with a hidden map they can't read. No one in that child's bloodline asked for the road we just built, and there's no off-ramp. We're not talking about a painting we can repaint; we're laying down a permanent foundation for every descendant to build on. That's why the bar has to be far higher than "cool."