Antigenic Correspondence of Serum Albumins among the Primates

The relative cross-reactivities as judged by tile quantitative precipitation reaction of 22 primate serum albumins were determined with pooled antiserums against human Serum albumnini. The atitgenic correspondences to human serum albumin of all but three serum albumin fell into narrow ranges, and the groups defined by these ranges are distinct taxonomic categories. The values of the cross-reactivity ranges are consistent with the presumed phylogenetic relationships to man on the assumption that the evolutionary modification of protein structure has been progressive and divergent.