And our bioinformatics analysis showed 7 hub genes (C5AR1, CXCR4, HCK, LAPTM5, MPEG1, TLR8, and TNFSF13B) were associated with those 4 AF-related immune cells, and these genes may be able to predict AF based on the ROC curve analysis (0.7 < AUC < 1). The gene discussed is CXCR4; the disease is atrial fibrillation.