The consistent reduction of CDKN1C relative to normal beta cells was confirmed both by DEG analysis as well as immunohistochemistry on a human insulinoma tissue microarray (Fig. 5e, f), and supports the putative imprinting abnormalities and CNV loss in the CDKN1C imprinted region on chromosome 11p15.5 (Fig. 4b). The gene discussed is CDKN1C; the disease is pancreatic insulinoma.