Interestingly, and as expected10, the regions of lower methylation in both beta cells and insulinomas overlap with key beta cell genes, such as INS/IGF2 and CDKN1C. We overlaid the methylation profiles of insulinomas and beta cells onto open chromatin regions in purified human beta cells, as defined by ATAC-seq analysis from the Human Pancreas Analysis Program (HPAP) database14 (yellow track). This evidence concerns the gene CDKN1C and pancreatic insulinoma.