The way I was taught in vet school is that an albino animal/human is one that is incapable of producing pigment. Now, in the reptile world, we have become accustomed to calling a white and yellow snake an albino. In fact it is not a TRUE albino as defined by lack of pigment. Animals have two different types of pigments that can be expressed at varying levels. The yellow/red pigments are known as pheomelanin, and the brown/black pigments are eumelanin. In the classic albino snake, what you have going on is actually a lack of the eumelanin... therefor the really should be called aeumelanistic rather than albino. What everyone said in the comments above about the tyrosinase is true, and will affect the color of the snake. Basically what I am saying is that the reptile/zoo world has been slack about terminology and so albino snakes are really not true albinos, but do lack certain pigments depending on the type of morph. A true albino snake would be pure white with pink eyes Hope this helps and makes sense!