Effect of the Environment in Reproduction and Embryogenesis
A growing body of data indicates that environmental exposures can be embodied within the developing male germ cell through epigenetic marks. In turn, these epigenetic marks may impart information at fertilization to affect the trajectory of development and offspring health. For example, nutritional manipulation in adult mice results in epigenetic dysregulation of sperm that affects offspring phenotype. These findings are significant because they provide evidence that environmental exposures encountered by adult males contribute to reproductive success via sperm epigenetics. However, relatively little is known about how adult exposures to toxicants affect sperm epigenetics and without such knowledge, advancing our understanding of paternal environmental determinants of reproductive health will be limited. In addition, embryonic development is highly susceptible to disruption by environmental conditions and chemical exposures, there are different windows of development that are more sensitive to these factors than others (i.e. germ cell development, organogenesis, etc.), and there are different mechanisms by which these factors exert their effects (epigenetics, oxidative stress, transcription factors, other signaling pathways, etc).