Gm (Ray), a New Allotypic Marker on Human IgG₃¹

Abstract

Abstract. A new antigenic determinant on the majority of human IgG 3 is described. The new antigen is found in the sera of all Gm(g)‐positive individuals and the majority of Gm(b)‐positive individuals. Only those individuals homozygous for Gm(c 5 ) are negative for the new antigen. Family studies verify the inheritance and indicate that the new antigen behaves as an alternate substitution to Gm(c 5 ) in man.