A Genetic Primer for Breeders - 2

For a breeder, understanding the inheritance of a trait that is controlled by several genes and influenced by the environment can be a nightmare. Suppose, for example, that you are trying to breed apricot Poodles, but instead of getting only a single shade, your litters always have a variety of shades from pale to dark apricot. You might blame it on variable expressivity, which is just a convenient way of saying that you don't know what other genes or environmental factors are also playing a role in determining the color.