Iba1 immunohistochemical analysis of the hippocampi from neonates revealed microglial morphological activation, as judged by the reduced proportion of ramified microglia (lean 65 ± 11% vs GDM 19 ± 6%), and an increased proportion of microglia exhibiting amoeboid morphology (lean 8 ± 2% vs GDM 46 ± 8%) (Fig. 3a–c). The gene discussed is AIF1; the disease is gestational diabetes.