In the present study, the levels of nAChR α7 and α4 subunit proteins (but no β2) in the hippocampus (CA3) of patients with T2DM were significantly lower than those in age-matched controls, with no significant differences in the case of the frontal or temporal cortex, indicating region specific alterations and subunit changes of the receptors caused by this disorder. Here, CHRNA7 is linked to type 2 diabetes mellitus.