Why You Should Breed
A breeder should be looking out for the whole dog, not just one aspect.
Why You Shouldn't Breed
Breeding can be intense, emotional and even traumatic. It is not to be done so lightly and uneducated.
Simply put, carriers are vital genetics and are essential to maintaining genetic diversity. Eliminating carriers from a breeding could cripple the gene pool. Carriers make up as much as 50% (or more) of the current genetic breeding pool. When breeding carriers you have to determine the risk VS value of breeding. You need to have a thorough understanding of the gene, the disorder it may cause, the quality of life for the offspring, the effect the gene has on the breed, if the gene can be safely bred out, the value the gene may have and the risk to the dam or sire. If you're breeding a VWD carrier you should know that the disease requires 2 defective genes to be an active disease risk/affected. A carrier is not at risk of a bleeding episode. Breeding a carrier is safe. What the carrier is bred to is the important part; a carrier bred to a clear will produce carries and clears (no defective gene). Each puppy has a 50/50 change of inheriting a VWD gene. A carrier bred to another carrier will produce affected puppies (two defective genes, active disease risk), carrier puppies (one defective gene, no disease risk), and clear puppies (two normal genes). A carrier bred to an affected will produce affected puppies and carriers. It is not advised to breed a VWD carrier to a VWD carrier, or ever breed a VWD affected dog.
There is a reason to breed a carrier to a carrier, however, you must thoroughly understand what you're doing. In the case of a DCM carrier bred to a DCM carrier it is deemed acceptable by current breeding practices. Nearly every Doberman carries one or multiple DCM gene mutations. The breed has too little diversity as it is; refusing to breed carriers could damage the breeding pool and future genetic diversity. The DCM genes are not directly linked to active disease and should be taken into consideration when looking for quality breeding dogs. A breeder should not base breeding a good dog solely on its DCM status. There are great dogs with phenomenal genetics that carry one, two or multiple DCM genes. Those dogs are too valuable to ignore their genetic diversity potential.