We performed another validation of BioAge as a predictive biomarker of the brain condition in elderly subjects both with and without AD using publicly available gene expression data from hippocampus samples (GSE1297). These data were used in prior research to qualitatively describe AD progression based on gene expression correlation with the disease severity, from control group through severe AD [31], [32]. We found that BioAge score calculated in these samples strongly and significantly correlated with the MiniMental Status Examination (MMSE) (ρ = −0.59, p = 4E–4). Figure S2A demonstrates the association between BioAge and AD severity. BioAge corresponded to the first principal component in this data set (ρ = 0.70, p = 1E–5), capturing a major source of gene expression variance and an overall brain condition.
