One Allele [g2m(n)] of the Human IgG2 Locus is More Productive Than the Other

Earlier investigators have shown that a high serum concentration of IgG2 and a high IgG2 antibody response to several polysaccharide antigens is associated with the allotype G2m(n) of the IgG2 subclass. We now show that the total IgG2 concentrations are significantly higher in G2m(n) than in G2m(–n) homozygotes (difference of means was 1.26‐fold, p = 0.002). Furthermore, in G2m(n) heterozygotes, the G2m(n) allele contributed more than the G2m(–n) allele to specific IgG2 antibody responses and to the total IgG2.