Cut and pasted from the AKC website.
http://www.akc.org/breeds/labrador_retriever/
Color
The Labrador Retriever coat colors are black, yellow and chocolate. Any other color or a combination of colors is a disqualification.
A small white spot on the chest is permissible, but not desirable. White hairs from aging or scarring are not to be misinterpreted as brindling. Black--Blacks are all black. A black with brindle markings or a black with tan markings is a disqualification.
Yellow--Yellows may range in color from fox-red to light cream, with variations in shading on the ears, back, and underparts of the dog.
Chocolate--Chocolates can vary in shade from light to dark chocolate. Chocolate with brindle or tan markings is a disqualification.
Mom taught me, let the pup pick you. If the pup with white spot is the one, then run it. (Of course, that's only my opinion) - My brown dog has a little white spot and the black dog has about 7 or 8 white hairs, and personally, I couldn't care less -999 out of 1000 of themhavegot SOMETHING about them that's not "desireable."