Fig. 4
Gene expression profiles related to the longitudinal cerebral atrophic differences of two MCI subtypes. (A) The correlation between regional PLS1 scores (weighted sum of 15,633 gene expression scores) and the T values of differences in longitudinal cerebral atrophy between two MCI subtypes. (B) The cortical maps of the subtype differences in cerebral atrophy as a function of follow-up time (subtype 1 vs. subtype 2). The color bar represents the T values without a threshold. (C) The cortical maps of regional PLS1 scores. The color bar represents the PLS1 scores without a threshold. (D-E) Genes positively weighted on PLS1 (e.g., NCOA3) are positively correlated with T values of subtype differences in longitudinal cerebral atrophy (r = 0.60, Pspin < 0.001), whereas genes negatively weighted on PLS1 (e.g., IFT22 and APOE) are negatively correlated with T values of subtype differences in longitudinal cerebral atrophy (r = -0.58 and r = -0.42, Pspin < 0.001). Bubble plots show the top 10 GO and KEGG pathways for the PLS1 + genes (F) and PLS1- genes (G), respectively. The bubble size represents the number of overlapped genes between the PLS1+ (or PLS1-) gene list and each GO term or KEGG pathway (y-axis). The x-axis represents the ratio of overlapped genes. The color bar represents the -log10(P) values (FDR correction). Abbreviations: APOE = apolipoprotein E; FDR = false discovery rate; GO = Gene Ontology; KEGG = Kyoto Encyclopedia of Genes and Genomes; PLS = partial least squares