I've known of the DNA question if you're unsure who has sired a pup but did you know...
What do you do if you are notified an AKC registered dog is not purebred?
If you would like to initiate an investigation of impure breeding, send us a letter with all information that you have about the puppy and the breeders. Describe, in detail, everything that causes you to think that there might be a problem. Please note that the dog in question must be at least 6 months of age. Include:
Pictures of your puppy (include at least a picture of the puppy in a standing position taken from the side at eye level and one that is taken head-on at eye level showing the face and skull structure)
Any other pictures that you feel would be relevant Copies of all registration information and/or sales agreements
Send the information to:
American Kennel Club
Attn: Impure Breeding
5580 Centerview Drive
Raleigh, NC 27606-3390
If you have specific questions about Impure Breeding, you can email:
kxw@akc.org http://www.akc.org/about/faq.cfm?page=8