Occurrence of quarter horses carriers mutations responsible for GBED, HM, PSSM1 and HYPP

Abstract

Quarter Horses (QH) are used in a variety of sports activities and large investments are made for genetic improvement of this breed. Molecular tests and determination of the occurrence of genetic diseases are critical for early identification of genetic abnormalities and to guide selection for reproductive purposes. Genetic-related muscular diseases of the QH include glycogen branching enzyme deficiency (GBED), malignant hyperthermia (MH), polysaccharide storage myopathy (PSSM1), and hyperkalemic periodic paralysis (HYPP). These diseases are caused by mutations in genes GBE1, RYR1, GYS1 and SCN4A respectively. Though the mutations responsible for these diseases have been already described, only the HYPP genetic test is available in Brazil. This research aims to study the mutation occurrence of GBED, MH, PSSM1 and HYPP in Quarter Horses. Blood and/or hair of 800 QH competing in cutting, conformation, racing, barrel racing and pole bending will be sampled. DNA will be obtained from the samples followed by amplification and sequencing of the specific mutation sites for the abovementioned diseases. The optimized molecular tests will allow both, selection of horses free of these genetic traits for mating, and diagnosis confirmation in clinically affected horses. (AU)