title: Evidence for a single pedigree source of the hyperkalemic periodic paralysis susceptibility gene in quarter horses.
abstract: The pedigree origin of a base pair substitution in the horse muscle sodium channel gene that confers susceptibility to the muscle disease hyperkalemic periodic paralysis (HYPP) was investigated with a set of 978 Quarter Horses. The horses were chosen at random, based on a collection of blood samples taken between 1989 and 1991 to meet parentage testing requirements, primarily but not exclusively from breeding stallions. The frequency of Quarter Horses positive for the base pair substitution, all heterozygotes, was 4.4%, which corresponds to an allelic frequency of 0.02. All horses positive for the gene traced to a single previously identified stallion as first, second or third generation descendants. A higher frequency of the HYPP susceptibility trait than expected by random occurrence was found among his descendants in this study.
authors.affiliation: Veterinary Genetics laboratory, School of Veterinary Medicine, University of California, Davis 95616-8744, USA.
authors.forename: A T
authors.initials: AT
authors.lastname: Bowling
authors.forename: G
authors.initials: G
authors.lastname: Byrns
authors.forename: S
authors.initials: S
authors.lastname: Spier
mesh_terms: D000818:Animals; D004198:Disease Susceptibility; D005787:Gene Frequency; D006580:Genetic Carrier Screening; D006734:Horse Diseases; D006736:Horses; D006947:Hyperkalemia / Q000235:genetics / Q000662:veterinary*; D008297:Male; D009132:Muscles / Q000378:metabolism; D010245:Paralyses, Familial Periodic / Q000235:genetics / Q000662:veterinary*; D010375:Pedigree; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D015222:Sodium Channels / Q000235:genetics*
chemical_list: D015222:Sodium Channels