Amel is designated by the exact pigment that is turned off, specifically Tyrosinase.
Let’s take Burmese Pythons. There’s Albino and Caramel. Albino in Burmese is Tyrosinase negative, which makes it technically Amel but it’s still a type of albinism. Caramel is Tyrosinase positive. It’s still a type of albinism.
In Retics, the most common Albino (purple, lavender, white, Mochino, etc) that reside on the same loci are Tyrosinase positive albinism.
Amel in Retics (and the other genes compatible on that loci) is Tyrosinase negative which is why Amels have red pupils versus a lavender which has black because there’s still the melanin producing enzyme Tyrosinase. Keep in mind, breeders name animals genes without genetically testing them. Amel in Retics isn’t named because of the color of the animal but because the original Amel was named Amelia. Any breeder can name a new morph whatever they want, even if it’s not ‘genetically’ true.
I’ve attached a side by side comparison of a Tyrosinase positive Lavender Albino Retic and a Tyrosinase negative Amel Albino Retic.
