Figure 3.

H19 and Igf2 expression in loxΔH19^Oocyte and loxΔH19^Mat mice. (A) The imprinting status of the Igf2 gene in liver and skeletal muscle of wild-type (WT) mice and mice carrying the loxΔH19^Oocyte deletion were examined by an allele-specific RNase protection assay. The Msp lane contains MspI-digested pBR322 as a size standard, and the Probe lane contains undigested probes. The 129 and Cast lanes contain liver RNA samples from the parental 129 and M. Castaneus mice. Mat and Pat refer to the parental origin of the RNase protection bands. (B) H19 RNA was analyzed by an RNase protection assay in wild-type (WT) mice and mice carrying the loxΔH19^Mat allele. (C) The imprinting status of the Igf2 gene in liver and skeletal muscle of wild-type (WT) mice and mice carrying the loxΔH19^Mat deletion was examined by an allele-specific RNase protection assay as in A. The loxΔH19^Δ13 lane contains liver RNA from a mouse with maternal inheritance of the H19^Δ13 deletion, where the maternal expression of Igf2 mRNA has been determined previously to be approximately 30% of paternal expression (8).