Tg(Rr28-Igf2)2Ddp

This transgene contains a 17 kb genomic fragment containing the entire coding region of a partially methylated mouse Igf2 under control of its own promoter. A small 5' fragment of the noncoding region of exon 1 was left out of this construct. The MluI restriction site at the 3' end of the nontranslated portion of exon 6 was abolished to distinguish the transgene from the endogenous Igf2 gene. A 7 kb genomic fragment containing the mouse Igf2/H19 enhancer sequences (Rr28) from downstream of H19 was cloned upstream of the Igf2 gene. RT-PCR analysis showed transgene expression equal to or slightly higher than the endogenous Igf2 protein in the liver, kidney, lung, heart, and mammary tissue. (J:90325)