The gene MYO15A is involved in the production of a protein included in the group of motor proteins known as myosins. Myosin XVA is located in the inner ear, the pituitary gland and other tissues, and has a substantial influence on the hearing process. Mutations in this gene cause amino acid substitutions in the conserved motor domain of the myosin chain, leading to shortening of the stereocilia in the hair cells, so that the function of myosin XVA is impaired. A research hypothesis was put forth that mutations in the gene responsible for the hearing process in animals of the Canidae family can cause hypoacusis, as well as substantial behavioural changes in dogs (ranging from timidity to aggressive behaviour). The study determined SNP polymorphism in a fragment of the gene MYO15A, which can cause hearing disorders or hypoacusis, in wild and farmed individuals of the Canidae family.