It does not seem possible that these two processes can coexist:
1) Genetic imprinting is the phenomenon where genes are expressed differently depending on the parent of origin:
1a. Methylated stretches of DNA are not transcribed.
1b. If the gene copy originating with mom is methylated but dad's copy is not, then only dad's copy will be expressed (e.g. Prader Willi syndrome).
1c. Methylation is preserved during cell divisions.
1d. Methylation is wiped at gametogenesis, when females will erase dad's imprints and re-imprint according to maternal imprint before meiosis.
But now I'm reading about the role of epigenetics in cell differentiation, and I discover:
2) Cell differentiation occurs with lineage-specific patterns of methylation.
2a. Immediately after fertilization (prior to the first cell division), the paternal genome undergoes demethylation.
2b. The maternal genome undergoes demethylation during the first few cell divisions.
2c. Cell differentiation is accompanied and perhaps even accomplished by progressive re-methylation following these "wipes."
Source for 2): http://labs.genetics.ucla.edu/fan/papers/HuangK_RM2010.pdf "DNA methylation in cell differentiation and reprogramming: an emerging systematic view" Huang & Fan (2010). Regen Med. 5(4):531-44.
I suspect that there is no conflict and I merely misunderstand one, the other, or both. Otherwise, how can a pattern of methylation be wiped both during gametogenesis and early embryonic stages and still be inherited?