Spark?

[ladywhipple02]

And yes it’s as u would call a base morph... it is like an albino, u can’t make an albino from anything but albino.

Not sure this is great example as Albino is a recessive gene meaning it's created by two animals carrying the dormant albino gene (hets). If you breed an albino to a normal, you get all normals looking animals that carry the albino gene. Spark isn't the same.

Pastel is a better example: if you breed a pastel to a normal, you get half pastels, half normals. If you breed two pastels, you get a super pastel. Same idea with spark/yellowbelly.

http://www.worldofballpythons.com/morphs/spark/