Mere dogs carry an inherited lethal gene. Not just Merle Great Danes, but aussies, doxies, border collies and any other breed that carries the Merle color gene. Two merle dogs of any breed bred together can and will produce puppies with many different kinds of birth defects. They are definitely 'full' Great Danes but because of the inherent defect in the genetic make up of the color they should not be bred or reproduced.