I am not an expert and don't know about how genes all mesh together but DR. White ( formerly Texas A&M I think dead now anyway) was an expert, here is a link to some articles he wrote there are some by others but his are there two. He was handed a very tight line bred family of Foxhounds his daddy left him and his grandpa gave his daddy he had both hands on & the science experience and I trust what he say's (not that it matters what i think ) and there are many others that produces a very high number of great dogs year after year. So thats who I ask about breeding, men who have had an unusualy high # of above average dogs of like traits and style that reproduce like dogs over and over.
http://www.foxhoundspastandpresent.com/breeding.html