Moreover, Chen et al., studied nine SNPs of the promoter region of CTLA-4 in 32 patients with ITP and showed no difference in + 49 A/G and CT60 A/G genotype between patients with ITP and HC, while a different SNP (rs11571315) was a susceptible SNP for primary ITP risk in the Taiwanese population [20]. The gene discussed is CTLA4; the disease is autoimmune thrombocytopenic purpura.