For example, analyzing the frontal cortex of patients with early, definite, and severe AD, Manczak et al. found an imbalance in mitochondrial dynamics with overexpression of the mitochondrial fission gene and downregulation of the fusion gene, likely due to the interaction between dynamin-related protein 1 (DRP1) and Aβ, suggesting a role of mitochondria in neuronal health and synaptic damage [50]. The gene discussed is DNM1L; the disease is Alzheimer disease.