While it is not clear whether such abnormal mitochondrial distribution contribute to neurodegeneration in the hippocampal and cortical neurons in Mfn2 cKO mice since some neuron population could survive almost complete loss of mitochondria from its processes [46], it could contribute to neuronal dysfunction such as synaptic deficits of importance to AD as we demonstrated before [9]. The gene discussed is MFN2; the disease is Alzheimer disease.