X inactivation Group, MRC Clinical Sciences Centre; Royal Postgraduate Medical School, Hammersmith Hospital
Beckwith-Wiedemann syndrome(BWS), a congenital overgrowth syndrome with a increased risk of childhood tumors. Familial BWS is inherited as an autosomal dominant trait and the BWS gene(s) is mapped to 11p15. Several lines of evidence indicate the BWS gene(s) is imprinted. Preferential loss of maternal 11p15 alleles is observed in several types of childhood tumors including Wilms' tumor, adrenocortical carcinoma, rhabdomyosarcoma and hepatocellular carcinoma, suggesting that genomic imprinting plays an important role. Possible models explaining BWS and tumor will be discussed.