American Quarter Horse Association - Registration

Registration

AQHA now registers the offspring of other American Quarter Horses in its numbered stud book. However, AQHA does not maintain a completely closed stud book; there is also an "Appendix" section. An "Appendix" American Quarter Horse is a first generation cross between a registered Thoroughbred and an American Quarter Horse or a cross between a "numbered" American Quarter Horse and an "appendix" American Quarter Horse. Horses in the "appendix" registry can "earn" their way into the main stud book by completing an extensive set of performance requirements in either racing or some form of show competition and receiving what the Association refers to as a Register of Merit (ROM).

Horses produced by means of artificial insemination or embryo transfer may be registered, but cloned horses cannot be registered. Parentage now is verified by means of DNA testing.

In recent years, registration requirements for AQHA have significantly changed. In the past, horses with too much white or with cremello traits were not eligible for registration. One reason was lack of a full understanding of equine coat color genetics (For example, people did not know that Palomino is an incomplete form of the cremello dilution gene) and the other was a legitimate a concern about a condition called lethal white syndrome, which was not fully understood at the time. There was also belief that excess white indicated "impure" breeding with non-Quarter Horses.

Today, modern DNA testing has now made verification of parentage possible, and also permits the detection of certain genetic diseases such as lethal white syndrome. Thus AQHA now allows registration of "high white" body markings typical of the sabino gene and other pinto spotting patterns. Many horses formerly registrable only as American Paint Horses with APHA are now cross-registered with both registries. Because the genetic mechanism that creates palomino is also understood and has been found to have no connection to lethal white, cremello and perlino coat colors are also allowed.

Cross-registration of American Quarter Horses with APHA, the Palomino Horse Breeders of America (PHBA), and the American Buckskin Registry Association (ABRA), is often a benefit to horses who have these distinct colors.

Currently, AQHA is in the process of phasing out registration of horses who carry the dominant genetic disease Hyperkalemic Periodic Paralysis (HYPP) and sponsored research that, in 2007, developed a genetic test for HERDA.