This imprinting domain harbors the paternally expressed non-coding antisense transcript to KCNQ1 called KCNQ1OT1, and other maternally expressed protein coding genes including KCNQ1 and CDKNIC1. Loss of imprinting, or hypomethylation, at the KvDMR1 has been widely implicated in the Beckwith–Wiedemann syndrome (BWS; Gaston et al., 2001; Diaz-Meyer et al., 2003; Azzi et al., 2009), a congenital disorder characterized by pre- and postnatal overgrowth, organomegaly, and a high risk of childhood tumors (Weksberg et al., 2010). Here, KCNQ1 is linked to Beckwith-Wiedemann syndrome.