Genetic polymorphism of a serum euglobulin of chickens which binds to antigen-antibody complexes

Binding of a euglobulin from normal chicken serum to precipitating HSA anti-HSA complexes has been demonstrated. The binding appeared specific for the Fc-fragment of chicken antibody since it was not detected with rabbit Ag-Ab complexes. Two allelic allotypic markers of the euglobulin under genetic control from one locus (E-1) were found in chickens from two inbred strains.E-1 alleles segregated independently from those controlled by theB (major histocompatibility),M-1 andG-1 (Ig allotype) loci. Partially purifiedE-1 had a sedimentation coefficient of 15.6 S. and-globulin electrophoretic mobility.Part of this work was done while one of us (CHT) was on sabbatical leave from the Department of Biomedical and Environmental Health Services, School of Public Health, University of California, Berkeley 94720, while on a Senior International Fellowship granted through the Fogarty International Center, National Institutes of Health, Bethesda, Maryland.