Basic Color Genetics: Black and Blue

Black and blue are in the same "B" family, the black is the dominant dense color while the blue is the recessive dilute color.   

Here is a black English Angora senior doe with a full coat.   The color genes are:
 aaB-C-D-E-.    
aa shows that black is a "self" color or a "non-agouti" pattern.  aa means it's "self" or "non-agouti".  B means it's in the black family, the - means there maybe another B gene or a b gene which is chocolate (we will talk about chocolate in a different post).    C indicates it's a full color, the - means there maybe another full color gene or some semi-colored gene or even an albino gene (will be discussed in a different post).    D indicates a dense color, the - means there maybe another dense color gene or a dilute gene.   E means the color is extended to the entire body, the - means there maybe another extension gene or a non-extension gene (we will talk about non-extension in another post).      The face keeps the black but the wool is lighter than black, more of a gray than black.   The color of the eyes is brown.

The lighting affects the color in the photo.  It's the same rabbit, Chu's Tamyra, in these two photos taken about the same time but at two different locations in our yard.   

The blue is the dilute of the black.  The color genes are:
aaB-C-ddE-
If you compare the black and blue genes, they are both aa which indicates "self" or "non-agouti", both are in the black family B, both are full colors C, both have extension gene E.  The only difference is at the "D" location.   The black is D- which means dominant, the - mains it could have another dominant gene or a dilute gene; the blue has dd which means double dilute gene thus shows a color that is diluted from black: blue.     The face of the blue rabbit is a dark gray, the body color is light gray and the color of the eyes is gray.    

 

Both photos are taken at the same time but still have a slight difference in color due to lighting.   The name of the rabbit is Chu's Talia.   
Since blue is recessive to black, two blue rabbits cannot produce a black offspring but two black rabbits could produce a blue offspring if both carry a dilute gene d.