HETEROGENEITY OF THE INHERITED GROUP-SPECIFIC COMPONENT OF HUMAN SERUM.

Heterogeneity of the group-specific (Gc) components in normal human serum has been demonstrated by the use of a lithium borate buffer system in conventional vertical starch gel electrophoresis and by prolonged immunoelectrophoresis in agar gel. In both Gc 1-1 and Gc 2-2 phenotypes a protein component migrates ahead of the main band. Immunological evidence indicates that the faster migrating band contains Gc specificity. The possibility that the two electrophoretically distinct Gc components share a common polypeptide chain is discussed.