The domestic dog (Canis lupus familiaris) is one of the most morphologically variable mammals and serves as an exceptionally intriguing model for exploring selection pathways. Research into its genetics is crucial for understanding the mechanisms of phenotypic trait inheritance, breed history, and the development of modern identification methods. Thanks to molecular genetic markers—particularly short tandem repeats (STRs)—it has become possible to distinguish individual animals and breeds effectively. This capability is actively utilized in studies of the genetic structure of dog populations, in the analysis of congenital disorders, forensic science, and canine breeding practices.