D1 form of Miniature dwarfism (D1)
D1 is one of the four tests in the ACAN panel. The ACAN dwarfism panel is relevant to pure and part-bred Miniatures, American Shetlands, and other breeds incorporating these bloodlines. It may also be relevant to other miniature horse breeds.
Horses that test positive for any of the tests in the ACAN panel should not be mated to other horses that have also tested positive. This is true even when they are positive for different tests, ie. one for D2 and one for D4. Foals with ACAN dwarfism are not simply smaller than usual. They can be born dead. They usually show deformities, including short twisted legs, a short neck, an abnormal head or a large abdominal hernia.
Ethical breeders can still breed from horses that test positive. Many of these horses are excellent. Keep dwarfism test results in context: they will add a moderate cost to your breeding program, but dwarfism carriers are much easier and cheaper to deal with than - for example - a horse with bad feet.
Gene or region and technical reference
Gene: ACAN (causative). Reference: Eberth et al. (2018)
n. Test developed using manufactured DNA, animal controls.
D1. Test developed using manufactured DNA.