I know of at least one YouTuber who took a homemade treatment that alerted his GI system DNA to produce lactase so he could eat pizza again:
That's not gene editing, but you could call it a gene therapy - he's introducing new fragments of DNA/RNA into his cells which then just float around and cause the right enzyme get made. Sometimes called upregulation. This is different to actually editing the existing DNA in the cell.
Good point - to be honest I didn’t realize the difference which is very significant from a treatment perspective.