Figure 1.

Experimental setup and study aim. Male wild guinea pigs (n = 5) were exposed for two months either to an altered diet (“experiment D”, left side, green) or to an increase in temperature (“experiment H”, right side, red). Each male mated with the same two females before (first mating, T_C) and after the period of exposure (second mating, T_D and T_H). Sons sired before the father’s environmental change represented the control groups (F1_CD = control diet and F1_CH = control heat), and sons sired afterwards represented the diet (F1_D) or heat (F1_H) group. We then analyzed DNA methylation patterns before and after the treatment to identify epigenetic inheritance. In the current study, we aimed to compare genes and gene pathways of the two environmental factors by comparing epigenetic diet effects versus heat effects.