Abstract

Genomic imprinting is an epigenetic marking process that confers parent‐of‐origin‐dependent expression on certain genes. These imprinted genes are sometimes found in clusters, suggesting a possible involvement of higher order regulatory elements controlling expression and imprinting of genes organised in such clusters. In the distal chromosome 7 there are at least four imprinted genes: Mash2, Ins2, Igf2 and H19. Recent evidence(1) suggests that imprinting and expression of at least Igf2 and H19 may be mechanistically linked.