APOE and early-onset autosomal dominant Alzheimer disease: ApoE type has not yet added clinically useful diagnostic information in conjunction with imaging; however, algorithms which include multiple biomarkers have been clearly shown to increase the power of studies and reduce the number of patients required to demonstrate the statistical significance of findings [61] and are encouraged by the Food and Drug Administration [63] and the Alzheimer’s Disease Neuroimaging Initiative (http://www.nia.nih.gov/research/dn/alzheimers-disease-neuroimaging-initiative-adni), which freely shares data.