OK guys, there has probably been more study done with labs and their colors, Black, yellow and chocolate than any other dog.
If you want to boggle your mind, read this
http://beulahland.tripod.com/coatcolor.htmI got started reading about it when I had 2 black Labs throw 6 yellows, 1 black and 1 chocolate in a single litter. THat link will tell you how many of each color you will get when you cross a gyp with these genes with a dog that has those genes. Pretty cool stuff.
And also in yellow lab there's a version known as a Dudley that has the recessive genes that cause pink noses and eyes. This is the way chocolate labs are, but when the recessive meets a recessive, you get Dudleys.
I am no geneticist , but I do know there are dominant genes that leave their mark either single or in pairs. White is the dominant hog hair color. I learned that in Ag and I crossed a york boar on several different colored sows and while the skin may be colored, the hair is white. Go to the county fair and look what color a York/Hamp cross is. White hair with black spots on the skin.
With recessive genes there has to be a pair for it to take over.
So if you are line breeding dogs with pink noses, it stands to reason that there will be pink nosed pups.
I have never studied up on glass eyes in dogs. It is probably interesting since you get 1 glass eye, 2 glass eyes a half glass eye. Its not by chance per say, but I guess it is by chance of what genes pair up.
