Fig. 2.

Genomic imprinting recapitulated in the humanβ-globin locus. (A) Total RNA was prepared from the spleens of anemic TgM (ICR or loxP lines). The relative expression level of the human β-globin gene (hβ), after normalization to that of the endogenous mouse α-globin gene (mα), was determined by RT-PCR. Data were collected from male (odd number) and female (even number) individuals, each inheriting the transgene either maternally (M) or paternally (P). The average and SD, determined by at least three sets of PCR reactions, are graphically depicted. Representative results of RT-PCR for hβ and mα signals are shown below each graph. (B) Total RNA was prepared from the liver (embryonic day 14.5; Left) and the yolk sacs (embryonic day 9.5; Right) of male (lanes 1, 3, 5, 6, 7, 9, 11, and 12) or female (lanes 2, 4, 8, and 10) embryos in two kinds of litters; one from the intercross of male TgM and female wild-type animals (P for paternal) and the other from the opposite combination (M for maternal). Representative results of RT-PCR analysis of the human ε (hε),γ (hγ), hβ, and mα expression in TgM lines ICR and WT are shown below each graph. The average and SD, after normalization to the endogenous mα gene signal, was determined as described in A. (C) Reprogramming of imprinting in the transgenic locus. Total RNA from the spleens of ICR-TgM was analyzed as described in A. Data were collected from male and female individuals, each inheriting the transgene either maternally (gray bars) or paternally (filled bars).