The role of epigenetic modification of gene expression is becoming increasi
ngly important in how we under stand the loss of tumour suppressor gene fun
ction in a variety of rumours and tumour predisposing syndromes. This revie
w explores the importance of epimutation in Beckwith-Wiedemann syndrome and
Wilms' tumour and focuses on genomic methylation in both imprinted and non
-imprinted genes as a key mechanism in the development of cancer. (C) 2001
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