[Homology between the Lpm system of allotypes in the American mink and the Gp system of allotypes in the domestic pig].

The 5 alpha-macroglobulin allotypes alpha M1, alpha M2, alpha M3, alpha M4 and alpha M5 were identified in pig. The alpha M1 allotype was reported as a marker of pig alpha-macroglobulin, the latter being homologous to alpha 2-macroglobulins in human and in mink. The allotypes alpha M2-alpha M5 were specified as markers of the second isotypical variant of pig alpha-macroglobulins, which was homologous to mink Lpm macroglobulin (alpha 1M). As seen from data obtained by International Comparative Test ISABR 87-88, alpha M1 is a new allotype, while allotypes alpha M2--alpha M5 correspond to four allotypes in the Gp system (Janik et al.). Based on these data, a conclusion was made on the homology between the Lpm system in american mink and the Gp system in pig. Since the allotypes studied are the part of alpha-macroglobulins, a locus controlling them was designated the AM locus. We also find it more advantageous to apply the same name to the homologous locus in mink, instead of the Lpm used earlier. Genetic control of 5 allotypes was studied and the structure of the AM locus in pig analysed in detail. Comparative study of organization of the above locus and the homologous locus in mink was carried out.