In the Aifm1 deficient Harlequin mouse model of mitochondrial disease, mice develop overt microgliosis with elevated levels of the proinflammatory cytokines TNFα and IL-1β in brain regions impacted by disease, reminiscent of Ndufs4(KO) cortical neuropathology but without the characteristic symmetric lesions [112, 122, 123]. This evidence concerns the gene NDUFS4 and mitochondrial disease.