Figure 3.

Illustration of intergenerational (F1) and transgenerational (F2) effects. The testis morphology shown demonstrates the cooperation of somatic cells and spermatogenic cells during spermatogenesis. Schematic of susceptibility windows for testicular toxicity in the F1 generation caused by prenatal exposure to nanomaterials (NMs), followed by the induction of potential toxicity mechanisms via the F1 germline to trigger transgenerational inheritance to the F2 generation, which is not subject to direct NM exposure. After mating with control females, phenotypic alterations are often observed in offspring in these paradigms. Illustrated here are a number of probable disease onset mechanisms underlying such paternal effects, including alterations in the sperm epigenome.