CD2 and atrial fibrillation: In this research, we identified 184 common DEGs between them, of which 14 were defined as hub genes, including LCK, HLA-DRA, ITK, CD2, CD52, GZMK, CD48, SLAMF7, CD247, KIT, IL2RG, NKG7, CD3D, and GZMA. Some of the above hub genes have been reported to play significant roles in DCM and AF.