White (Introduction)

White (which is recessive) is a bit of a special case in the genetics world - it is not a colour, but lack of pigment in the coat. There are several genes that will affect how the white developes on a dog, but it's not known exactly how they work at this time. For instance, we don't know what causes white dogs with blue eyes to pop up, or whether there are any true albinos in the dog world (so far DNA tests of supposedly albino dogs have not shown a mutation in the gene that causes albino in other animals).
Some solid white dogs have a slightly ceamish sheen to their white. They are not pure white, but more of a very, very pale cream and fall into the red category rather than being "truly" white.
Some dogs are white with deep black pigment on the nose and around the eyes, like samoyeds. These dogs are believed to be an interesting case where the dog is unable to produce both red and black in the coat, leaving it white. These dogs do not suffer from the same problems (mainly deafness) which is found in some other white breeds.

Sometimes, otherwise solid dogs can be born with a little bit of white, for instance on the chest or tailtip. These small markings are not caused by a special gene, but could be formed by something as easy as the fetus laying a certain way in the womb. It is only when when we speak of several 'real' white markings, such as white feet and chest, or even a patched appearance, that there are white spotting genes at work.