Lo et al. (2011) assessed the relationship between the longitudinal change of biomarkers (e.g., Aβ42 level in CSF) and hippocampal volume, as well as the presence of the APOE4 gene, on cognitive decline in 193 subjects with AD, 397 subjects with MCI, and 229 normal-aged control subjects from the ADNI database (Table 1). This evidence concerns the gene APOE and Alzheimer disease.