I’m having trouble digging up info on these. Searches on the forum here are a bust.
X-treme was proven by Ken Macek and there’s a single super X-treme example on WoBP. Supers have a very nice stripe and non-supers seem to have a busy pattern.
Gene-X was captive produced by J Kobylka in a pied line. I’ve seen his examples of non-pied normal Gene-X but not much more. It’s not super obvious to me what this combo does other than (via jkr) giving pied brighter colors.
Any descriptions or pictures handy?