Craniofacial development is under genetic control and virtually all malocclusions are genetic and heritable. One possible exception would be a “wry-bite” or facial asymmetry secondary to a known trauma during development. In the absence of a known trauma that could reasonably be expected to have caused the deformity, all malocclusions should be considered genetic and heritable. Affected individuals should not be bred and neither should their parents. It might even be best to avoid breeding their litter mates.