Genetic heterogeneity of rabbit alpha-1-antitrypsin.

Sixteen inbred or partially inbred strains of rabbits were investigated for electrophoretic and quantitative variations of alpha-1-antitrypsin (A-1-AT). We found interindividual differences in the electrophoretic A-1-AT patterns as well as quantitative differences in the concentrations of A-1-AT and the serum trypsin-inhibiting activity. Three electrophoretic phenotypes were distinguished: M, P and MP. M was characterized by a predominant anodal A-1-AT band, and P had a major cathodal component. The MP pattern can be explained by the occurrence of the M and P components in the same serum due to heterozygosity. The P pattern was associated with an A-1-AT concentration of approximately 56% of that in sera with the M phenotype. The levels of A-1-AT in sera with the MP phenotype were intermediate between those in M and P types. In addition to the type-specific quantitative variation, we found a quantitative sexual dimorphism of a moderate degree: Female rabbits had A-1-AT concentrations 16% less than males.