Epigenetics and fetal adaptation to perinatal events: diversity through fidelity.

Perinatal insults, including fetal undernutrition and hypoxia, are associated with an increased susceptibility to several adult-onset metabolic disorders. These include cardiovascular disease, insulin resistance, and obesity. However, the mechanisms driving the long-term phenotypic consequences have only recently begun to be elucidated. A primary mechanism accounting for perinatal adaptation is the epigenetic modification of chromatin. In this context, epigenetic modifications to chromatin are thought to arise in response to a perinatal insult in an effort to modulate gene expression and maximize fetal survival. In this symposium report, we discuss epigenetics as a mechanism by which perinatal adaptations can be made by the developing fetus. We examine the benefits of using multiple in vivo models to understand the interrelation of signals that come together and result in perinatal adaptation. Epigenetic effects on IGF-1 arising from a perinatal insult are discussed, as are the difficulties and challenges associated with this complex field. In conclusion, epigenetics provides a means of modulating gene transcription, thus allowing fetal adaptation to a broad variety of conditions.