SALL4 is recognized as the causal gene in the hereditary diseases Duane Radial Ray syndrome, Okihiro syndrome and Holt–Oram syndrome [54–56], which share several common characteristics with thalidomide embryopathy [57]. Considering the partial structural similarity of TFBP (1C) and TFNBP (1D) with thalidomide-analogue drugs (1A and 1B), we analyzed their interaction with cereblon through a cereblon/BRD3 binding FRET assay. Here, SALL4 is linked to Okihiro syndrome.