Imprinting of the maternally-expressed Igf2r gene is controlled by an intronic 
imprint control element (ICE) known as Region2 that contains the promoter of the 
noncoding Air RNA, whose transcript overlaps the silenced paternal Igf2r 
promoter in an antisense orientation. Two novel imprinted genes, Slc22a2 and 
Slc22a3 are described here that lie 110 and 155 kb 3' to Igf2r and that are not 
overlapped by the Air transcript but are regulated by the Igf2r-ICE, as 
previously shown for Igf2r. These results identify a new cluster of imprinted 
genes whose repression by the bidirectional action of the Region2-ICE is 
independent of transcript overlap by the Air RNA.