It's my understanding that many "Iowa" albinos really aren't just Iowa anymore and the term is now just used on any T-. They aren't just descended from the original Iowa albinos. At some point, the Iowa was crossed with another T- from a different state and the two proved to be compatible. The orange color then popped up in the descendants but I don't think anyone is certain where this orange gene came from. With the red one's it's simple. They are red phase and albino. But there is no "orange phase" normals. There are no radixes with this shade of orange that are not albino. Kind of a mystery.

I did notice though, that the normal looking female I have from this line, has tiny flecks of orange showing through the normal color but you really have to look close and expect it in order to see it. I wonder if this particular orange gene is something that is normally hidden underneath layers of melanin and is only revealed once you take that away.