In the year 1969 a 15.1 hand, sorrel, Quarter Horse was born, of the name Impressive. At the age of seven he was a World Champion Open Aged halter stallion. Being such a progeny he sired 2,250 foals, and nearly thirty went on to be World Champions themselves. He was the beginning of something big, something that would affect the genetic makeup of Quarter Horses for centuries. Impressive is the founder Hyperkalemic Periodic Paralysis, also known as HYPP. HYPP is a major issue in American Quarter Horses and a concern in the (AQHA 2010).

Hyperkalemic Periodic Paralysis is an inherited disease of the muscle, which causes trembling and shaking of the muscles and can lead to weakness and collapse. In the muscle of the affected horses, a point mutation exists in the sodium channel gene and is passed on to offspring (Horse 2008). The sodium channels are pores or openings in the muscle cell membrane, which control contraction of muscle fibers. When the horse has the HYPP gene it causes the sodium channel to become leaky which causes the muscle to be overly excited and contract involuntarily. The channel becomes leaky from fluctuating levels of potassium …show more content…
As of 1996 horses that may carry the HYPP gene can no longer show in AQHA shows.(AQHA 2010) Because of this regulation many owners and breeders lost a significant amount of money. Even though horses with HYPP have good muscle and desirable traits, they can no longer breed or show theses horses, resulting in the horse not bringing in any money. On the upper hand, we can save other people's money by having horses tested for HYPP. To test a horse for HYPP there must be a DNA test on the hair roots by a licensed laboratory. The cost to test for HYPP is around $40. If horses are tested we can prevent future generations from having HYPP and the loss of money gone into the process of breeding a mare, training the foal, and possibly death of the