Despite LD between FCGR3B CNV and a variant in FcgammaRIIB (I232T) which abolishes inhibitory function, both reduced CN of FCGR3B and homozygosity of the FcgammaRIIB-232T allele were individually strongly associated with SLE risk.
Recent work has enhanced our understanding of the mechanism of action of the FcgammaRIIB I232T polymorphism and the overall role of this receptor in SLE.
We recently identified a single-nucleotide polymorphism encoding a non-synonymous substitution, Ile232Thr (I232T), of FCGR2B and its association with SLE in Japanese and in Thais.