HCG18 and Alzheimer disease: Four lncRNAs (XIST, NEAT1, KCNQ1OT1 and HCG18) and four miRNAs (hsa‐let‐7c‐5p, hsa‐miR‐107, hsa‐miR‐129‐2‐3p and hsa‐miR‐214‐ 3p) were identified as potential biomarkers for AD.