Well, first, I am sorry if you don't understand. My first language is french and not english, when I typed it yesterday it was late and it was just after a long day at work and university and watching a hockey game (with some beers).
You are right on what you are saying but that's not what I was trying to say.
I was trying to say that a albinism gene (T-) can differ from one species to another.
That geneticly they doesn't look the same (chromosome) but their effect are the same on the animal (not produce melamine).
A bit like the Cold virus (I know it's not a gene but it can help you understand what I am trying to say). There is a lot of variation of it, but the effect of it is the same.
The T- in the tiger/alligator/ball/burmese all have the same effect, keep the skin from producing melamine, but I am pretty sure if we were able to look at them under a microscopre, they wouldn't look the same and probably wouldn't been on the same loci.
Making the cross between both species (both showing albinism) not being albinos but het or double het.