Melanin is a class of proteins found in many plants and animals that usually acts as a pigment. Humans produce two forms of melanin, one that is brown-black in color and one that is red-brown in color, that account for skin color, eye color, hair color and other pigmentation. These are produced in varying quantities by the vast majority of people, but are controlled by several genes which account for the wide variety of coloration. Albinism is a group of genetic disorders that prevent the body from synthesizing melanin.