These results indicate that IDH1/2 mutations did not lead to the diffuse enhancement of promoter CpG island loci but instead to the selective enhancement of specific CpG island loci, which was evidenced in Kwong et al.’s study, which analyzed the genome-wide methylation statuses of 38 cases of cholangiocarcinoma using the Illumina 450 K Infinium bead assay23. The gene discussed is IDH1; the disease is cholangiocarcinoma.