Table 1

Comparison of the two major alleles of FcγRIIa. The affinity for IgG3 is slightly higher for the H-131 allele

AlleleAffinity for human IgG subclassesAmino acid differencesCorresponding nucleotide differences
R-131IgG3=IgG1>>IgG2>IgG427 Glu 131 Arg236/7 CA 519 G
H-131IgG3>IgG1=IgG2>>IgG427 Tyr 131 His236/7 TG 519 A