[Formation of a gene pool of miniature Siberian swine "Minisibs" and their use in medico-genetic research].

The results of 35-year breeding of a new variety of laboratory animals for biological and medical studies, termed Minisibs (miniature Siberian swine), are summarized. Minisibs were obtained via hybridization between Swedish Landrace pigs, who have an epistatic white coat color, and black Vietnamese masked pigs of breed I, who have genes of dwarfism. Some genes of wild boars Sus scrofa scrofa and S. s. nigripes from Central Europe and Central Asia, respectively, were introduced to the Minisibs gene pool in order to strengthen the constitution, increase the general resistance, and improve the functions of the cardiac muscle and valves. The pigs were selected for a decrease in body weight and an increase in litter size over 15 generations. Immunogenetic and chromosomal polymorphisms were constantly monitored by Robertsonian translocations Rb 15/17 and Rb 16/17 introduced from boars. Long-term breeding produced a population of laboratory pigs with an average adult weight of approximately 60 kg, a litter size of seven to eight piglets, and quiet behavior. Most of animals used in selection were white, which is essential for radiobiological experiments and studies on skin histocompatibility. Introduction of chromosomal polymorphism to the minipig gene pool and long-term immunogenetic and cytogenetic monitoring made it possible to perform subchromosomal mapping of the loci of some blood-group systems associated with the loci controlling coat color, litter size, stress resistance and meat quality (halothane sensitivity), and histocompatibility. Minisibs have been successfully used in numerous biomedical studies and in therapeutic and surgical cardiology (for production of diagnostic sera controlling lipid metabolism and of biological prostheses of cardiac valves). The anatomical and physiological similarity of Minisibs to humans indicate that these animals may serve as donors of xenografts for orthotopic heart transplants to humans.