IGF2 and Silver-Russell syndrome: Most SRS patients carry molecular changes in the 11p15.5 region (Fig. 1B), the most prevalent (~50%) of which is hypomethylation of the DMR H19/IGF2:IG-DMR (hereinafter referred to as ICR1), decreasing paternal IGF2 (a potent fetal growth factor) expression and increasing the maternal expression of H19 (10), encoding a lncRNA.