Demethylation of DMR-LIT1, an imprinting control region (ICR) of the KIP2/LIT1 domain, occurs in half of all patients with Beckwith–Wiedemann syndrome (BWS) (OMIM 130650), which predisposes patients to embryonal tumours, and in a variety of adult tumours. Here, KCNQ1OT1 is linked to Beckwith-Wiedemann syndrome.