CDKN1C and Beckwith-Wiedemann syndrome: The human imprinted gene CDKN1C is the most frequently silenced or mutated gene in the imprinting genetic disorder Beckwith-Wiedemann syndrome (BWS); aberrant imprinting of IGF2 has also been shown to interact with CDK1C in this imprinting disorder (Caspary et al., 1999; Grandjean et al., 2000).