CYP11B1 and adrenal gland neoplasm: To examine the role of DNA methylation on high CYP11B1 expression in CPA, we compared the DNA methylation level of five CpG sites in the CYP11B1 promoter (Fig. 2a, Figure S6) in CPA with the same sites in AUAT, white blood cells (WBC), zona fasciculata (ZF) of normal adrenal cortex, non-functioning adrenal tumor (NFT) and H295R cells.