FIGURE 1.

Transgenerational inheritance of disease risk: evidence from animal models. Gestational exposure of mice to an environmental trigger, in this case, diesel exhaust particles (DEP) or concentrated urban air particles (CAP), leads to increased asthma risk in up to 3 generations of offspring. It is important to distinguish intergenerational inheritance from transgenerational because in a gestational exposure model not only the pregnant F0 ancestor is directly exposed to the trigger, but also the fetus; moreover inside the F1 fetus there are predecessors of gametes that will give rise to F2 progeny which are theoretically also directly exposed. In the paternal line only the predecessors of gametes that form the F1 are directly exposed and effects that persist to the F2 can be considered transgenerational