Allele frequency of variants associated with HERDA and GBED in bull-catching (vaquejada) Quarter Horses

Abstract

The Quarter Horse (QH) breed represents a prominent cohort in equestrian sports, demonstrating remarkable versatility across various disciplines. Notably, it excels in bull-catching (vaquejada), a sport characterized by brief yet high-intensity exercise. Vaquejada holds substantial significance within the equine industry, encompassing approximately 13% of sport horses in Brazil, particularly in the Northeast region. The Five Panel, consisting of five genetic diseases mandated for testing by the Brazilian Quarter Horse Breeders Association (ABQM) for animal registration, addresses crucial aspects of equine health. Our recent investigation focused on the prevalent muscular genetic diseases (MYHM, HyPP, PSSM1, and MH) within a population of QH vaquejada athletes from Northeastern properties. However, two vital diseases within the Five Panel, namely Hereditary Equine Regional Dermal Asthenia (HERDA) and Glycogen Branching Enzyme Deficiency (GBED), were not explored. Both HERDA and GBED exhibit an autosomal recessive pattern, with HERDA being the principal genetic skin disease and GBED being the primary condition associated with stillbirths and abortions in QH. This study aims to assess the allele frequencies of HERDA and GBED in vaquejada QH. A total of 100 QH sourced from breeding farms in Northeast Brazil will be employed for this purpose. Genotyping will be conducted through Sanger sequencing for both variants, followed by the calculation and determination of allelic frequencies.