Hanna et al. proposed a 325 kb critical region for brain malformation and intellectual disability, comprising the DLL1 (OMIM 606582), PSMB1 (OMIM 602017), TBP (OMIM 600075), and PDCD2 (OMIM 600866) genes (Hanna et al., 2019). The gene discussed is DLL1; the disease is Intellectual disability.