There are nearly nineteen thousand genes in a dogs genome but scientists believe that only eight of them determine coat color.
A dogs coat is colored by three pigments that interact with each other.
The list is as follows:
Black chocolate brown or gray eumelanin
The phenomenon pigment is either gold tan or red
White because of lack of melanin
There are eight genes that determine if these colors are present and how they are distributed across a dogs coat.
Golden retrievers have mostly pheomelanin pigments while eumelanin and melanin pigments are recessive.
In order for "rogue" colors to appear a gene must slightly malfunction.
Compared to that humans have twenty to twenty-five thousand genes (that we know about at the moment) and 124 of these are involved in determining our hair color.