Aberrant imprinting leads to developmental disorders, including Beckwith-Wiedemann syndrome (BWS: OMIN130650), Angelman syndrome (AS: OMIN 105830) and Silver-Russell syndrome (SRS: OMIN 180860), which are associated with imprinted genes including H19/IGF2, SNRPN and KCNQ1OT1[15–17]. The gene discussed is KCNQ1OT1; the disease is Beckwith-Wiedemann syndrome.