FGF21 and major depressive disorder: To explore the connections between the expression profiles of 23 PS genes (CLEC5A, CAMP, TLR2, ADORA3, NLRP3, CD14, CD274, NLRC4, NAIP, CAPN1, GPER1, VDR, FGF21, IL1RN, FOX O 3, SERPINB1, ATF6, HMGB1, POP1, IRGM, BIRC3, GZMA, and UTS2) and MDD subtypes, we performed unsupervised clustering using data from 64 MDD cases.