by PawVillage.com staff

How do the Aussie coloring genetics work? That can be simplified to two seperate questions, whether the puppy is black or red, and whether it is merle or solid. All of the four combinations may or may not have white and copper markings. For black vs. red, the black gene is dominant. For merle vs. solid, the merle gene is an incomplete dominant gene. The diagrams below show how a dog will look with each of the possible gene combinations:

Black vs. Red BB Br rr

Merle vs. Solid MM Ms ss

A dog with a double merle gene (homozygous merle) will often be excessively white and will usually develop health problems, for example deafness and blindness.

This picture shows the four different combinations.
Clockwise from top left: Black, Red, Red Merle, and Blue Merle.

Possible Color Crosses
Br x Br   B r B BB Br r Br rr		Br x BB   B r B BB Br B BB Br		Br x rr   B r r Br rr r Br rr
BB x BB   B B B BB BB B BB BB		BB x rr   B B r Br Br r Br Br		rr x rr   r r r rr rr r rr rr

Possible Merle/Solid Crosses
Ms x Ms   M s M MM Ms s Ms ss		Ms x ss   M s s Ms ss s Ms ss		ss x ss   s s s ss ss s ss ss