While mutations in most of the CHD proteins have been described and demonstrated to lead to a range of cancers and developmental diseases (Table 1) [13,27,40,54,58,59,65,66,71], a number of gene variants in the gene encoding CHD2 were identified as the cause of a developmental epileptic encephalopathy (CHD2-DEE) [16,17,18,19,20,21,73]. This evidence concerns the gene CHDH and cancer.