What's your Diagnosis?Answer: Hyperkalemic periodic paralysis (HYPP) HYPP is a genetic condition of malfunctioning sodium channels in muscle cells. It is primarily seen in Quarter Horses, or related breeds, of the Impressive lineage. The condition arose from a spontaneous mutation in DNA which is passed onto offspring in an autosomal dominant matter, and the AQHA regulates breed registration of homozygous horses. Horses which have the gene may display varying levels of clinical signs including m