In our study, we found for the first time that cryptococcal meningitis was associated with the FCGR2B 232I/T genotypes, which was not reported in Metediatis' study. As the only known inhibitory FccR, FccRIIB has an immunoreceptor tyrosine-based inhibitory motif (ITIM) in its cytoplasmic domain, and thus it plays an important role in regulating the immune system [40] . FCGR2B 232I/T is located in the transmembrane domain, and the FccRIIB receptors encoded by FCGR2B 232T are unable to interact with activating receptors and exert inhibitory activity [38] . Published data have suggested the mutation genotype FCGR2B 232T/T to be a susceptible genotype for systemic lupus erythematosus [17, 22, 32] , and this genotype also provided protective effect for severe malaria in East African children [17] . The role of FccRIIB in cryptococcal infection is still not very clear. Like the activatory FccRs, FccRIIB can also recognize the major component of the capsule of C. neoformans, glucuronoxylomannan (GXM). In a previous study by Monari et al., the immunosuppressive effect of GXM was demonstrated to be dependent on FcRcIIB, based on the evidences that FccRIIB blockade inhibits GXM-induced IL-10 production and induces TNF-a secretion, and that the addition of monoclonal antibody to GXM reverses GXM-induced immunosuppression by shifting recognition from FccRIIB to FccRIIA [41] . Another study subsequently demonstrated that GXM triggered NO-induced macrophage apoptosis, which was dependent on FccRII [42] . These data support that FccRIIB plays a critical role in the pathogenesis of cryptococcal infection. In our study, it is the FCGR2B 232I/T heterozygote instead of the minor homozygote 232T/T that is under-presented in patient group. One study on children with idiopathic thrombocytopenia (ITP) also showed a similar pattern, that the FCGR2B 232I/T was less frequently detected in acute ITP in comparison with chronic ITP [27] . The reason for the heterozygotes 232I/T rather than 232T/T under-presenting in our patients and those acute ITP children has not been clarified.