There are also close interactions between the loss of mitochondrial metabolism and cholinergic neuron degeneration in APP/PS1 AD mice, which, at the age of 6–8 months, displayed Aβ deposits and cognitive deficits accompanied by losses in cholinergic neurons, ChAT, VAChT, choline and NAT levels in the hippocampus and medial septum. The gene discussed is APP; the disease is Alzheimer disease.