Inflammatory cytokines and low-affinity Fcγ receptor (FcγR) polymorphisms were investigated in 37 children with chronic immune thrombocytopenic purpura (cITP) and 218 controls. Genotype analysis included common variants in the regulatory regions of cytokines, TNF, LTA, IL1RN, IL1A, IL1B, IL4, IL6 and IL10, and structural variants of the low affinity FcγRs, FCGR2A, FCGR3A and FCGR3B. Associations were observed for TNF (P = 0·0032), LTA (P = 0·019), FCGR3A (P = 0·038) and FCGR3B (P = 0·0034). Two combinations of genotypes (TNF and FCGR3A;P = 0·0003, and LTA and FCGR3B;P = 0·011) were significantly associated with cITP. These results provide preliminary evidence that variant genotypes of FcγRs and cytokines contribute to cITP pathogenesis.