Loss of function of CDKN1C, seen most often in familial BWS, has been modelled by the generation of three independent Cdkn1c mutant alleles, which recapitulate some aspects of the disorder (Takahashi et al., 2000; Yan et al., 1997; Zhang et al., 1997). Here, CDKN1C is linked to Beckwith-Wiedemann syndrome.