The Solid Black is dominant, or BB. The Landseer is recessive to the solid black, or bb, and is the result of the piebald gene, which places the self-color on a white background. Solid Bronze is recessive to black, and the Solid Gray is a dilute of black. Care must be taken when matching dogs with recessive genes, as the piebald gene will result in a solid color and white dog. Where the solid color is black, the Landseer results, which is a color allowed by the standard. However, if dogs with Brown or Gray backgrounds are bred with a Landseer, the possible results are a Bronze and White or a Gray and White dog, both of which are explicitly disqualified in the standard. (Note that ‘solid’ color is considered by the standard to include some white.)