Spearman’s analysis of possible correlation between TET1 methylation at 30 CpG probes and TET1 expression revealed the methylation at 4 CpG sites in NOR (one in the promoter and 3 in the 5′-UTR) and 10 CpG sites in PCa (4 in the promoter, 3 in the 5′-UTR, and 3 in the gene body) to be significantly correlated with TET1 expression (Fig. 2A.1 and Additional file 2: Table S3). The gene discussed is TET1; the disease is posterior cortical atrophy.