They found that ApoC3, beta‐2‐glycoprotein 1, C4b‐binding protein alpha chain, complement C3, and immunoglobulin kappa variable 2–30 were significantly increased in controls, whereas alpha‐1‐antichymotrypsin isoform 1, CO9, IGHM, isoform 2 and keratin, type II cytoskeletal 6A (K2C6A) were significantly increased in AD cases. Here, C3 is linked to Alzheimer disease.