Look at any cat and you’ll often see different colors mixed together such as a black and white cat or a brown and white cat. Whatever the color, the pattern of different colors determines more than just color. Piebaldism, which usually displays white areas of fur, hair or skin due to the absence of pigment-producing cells in those regions, can also be important to understanding diseases.
In normal development, pigment cells start near the back of the embryo and spread through its developing skin to the belly. As the cells spread and multiply, they create more cells, some of which are left behind to ensure all the skin is pigmented. In piebaldism, there simply aren’t enough cells to pigment all the areas of a developing embryo. The result are patches of white.