Tortoiseshells and dilute tortoiseshell cats are not actually breeds of cat, but a color pattern that can occur in many different breeds, namely American and British Shorthairs, Maine Coons ...

A prime example of X inactivation is in the coat-color patterning of tortoiseshell or calico cats (Figure 1). In cats, the fur pigmentation gene is X-linked, and depending on which copy of the X ...