The topaz mutation is characterized by modification of eumelanin production; By concentrating this around the core center of the plumage, which allows the appearance of long, clear contours on large springs and hidden springs, the absence of ethanein increases the brightness of the lipochrome background.
This factor reduces and modifies black eumelanin, which also reduces euphelanine. The mutation acts on the beak, legs and nails, which gives a brown tone more or less clear depending on the variation, in the eye seems to cause a slight dilution. Genetic behavior is autosomal and recessive in classic melanomas and codominant in the rubino mutation.
