For example, the loss of maternal imprinting of the insulin-like growth factor 2 gene, IGF2, accompanied by its increased expression, is the most common genetic or epigenetic alteration in Wilms tumors, an early driver event in the development of ileal neuroendocrine tumors (I-NETs), and has protumorigenic effects in many other cancers [53–57]. The gene discussed is IGF2; the disease is Wilms tumor.