FGF21 and Alzheimer disease: Among them, the gene expression levels of UBAC2, FBXO17, UBE4B, TMEM67, CREB3L3, RNF103, TMEM117, DNAJC10, and SEL1L2 were markedly greater, RNF186, NGLY1, AGR2, RNF5, SERP2, DDX3X, FBXO27, and FGF21 expression levels were significantly lower in AD patients than that in non-AD normal individuals (Figures 2D,E).