Figure 3.

Epigenetic defects caused by preconception ZD. A 3–5 day period of dietary ZD is sufficient to cause a reduction in DNA and histone methylation and increased abundance of transcripts from the repetitive elements in the oocyte. These defects are associated with impaired preimplantation development, including reduced abundance of Igf2/H19 transcripts and impaired trophoblast differentiation. However, even later in pregnancy after normal dietary zinc status is restored, defects in placenta formation, fetal survival, and fetal development persist, suggesting a long-lasting impairment of developmental potential.