Figure 4.

Paternal and maternal imprinted regions and their default states of expression. Expression profiles of imprinted genes in somatic cells (A and F), day 12.5 PGC cloned embryos (C), androgenetic (D) and parthenogenetic embryos (E) are illustrated. The black, blue and red circles represent normal biallelic, paternally and maternally expressed genes, respectively. There are two types of imprinted regions, paternally (right blue) and maternally (pink) imprinted regions, where the paternally and maternally-derived DMRs are methylated, respectively. Erasure of imprinted memories occurred in PGCs and the paternal and maternal imprints established during spermatogonia development around the time of birth and oocyte maturation after birth in the male and female germ lines, respectively. Modified from Fig. 2 in ref. 14.