Overall, activating receptor SNPs with increased IgG binding (FcγRIIA-131H, FcγRIIIA-158V) are associated with reduced susceptibility to infection [15, 86], whilst a reduction in FcγRIIB activity increases defence against bacterial [50, 81••, 87], mycobacterial [88], viral [89] and parasitic inf﻿ection﻿ [83, 84]. This evidence concerns the gene FCGR3A and infection.