Affected dogs are usually clinically normal though an increased susceptibility to infections, especially fungal and bacterial infections, has been associated with the disease. The disease might also predispose an affected dog to neoplastic and neurodegenerative changes. The disease is caused by the deficient or absent function of the myeloperoxidase enzyme in neutrophils and monocytes.

Therapy is targeted at treating the secondary infections.

There are many responsibilities to consider when breeding dogs. Regardless of test results it is important that your dog is in good general health and that you are in a position to care for the puppies if new responsible owners are not found. For first time or novice breeders, advice can be found at most kennel club websites.

This disease is autosomal recessive meaning that two copies of the mutation are needed for disease signs to occur. A carrier dog with one copy of the Myeloperoxidase Deficiency mutation can be safely bred with a clear dog with no copies of the Myeloperoxidase Deficiency mutation. About half of the puppies will have one copy (carriers) and half will have no copies of the Myeloperoxidase Deficiency mutation. A dog with two copies of the Myeloperoxidase Deficiency mutation can be safely bred with a clear dog. The resulting puppies will all be carriers. Puppies in a litter which is expected to contain carriers should be tested prior to breeding. Carrier to carrier matings are not advised as the resulting litter may contain affected puppies. Please note: It is possible that disease signs similar to the ones caused by the Myeloperoxidase Deficiency mutation could develop due to a different genetic or clinical cause.