In one aspect, methods of diagnosing a subject as having Alzheimer's disease and prognosing a subject as being at risk of progressing to Alzheimer's disease are provided. In some embodiments, the method comprises determining one or more of the level of expression of rhotekin 2 (RTKN2), the level of expression of microtubule-associated Ser/Thr kinase 4 (MAST4), the level of binding of forkhead box O1 (FOXO1) to the RTKN2 promoter, and the level of binding of amyloid precursor protein (APP) to the MAST4 promoter in a sample from the subject.