Bull fetuses exposed to maternal overnutrition experienced a decrease in expression of steroidogenic acute regulatory protein (StAR), hydroxysteroid 17-Beta dehydrogenase 3 (HSD17B3), IGF1, IGF2, and IGF1 receptor (IGF1R), genes involved in testes development and steroidogenesis [68]. The gene discussed is STAR; the disease is overnutrition.