FCGR2A and Kawasaki disease: We also investigated several genes that are known to be associated with Kawasaki disease and play a crucial role in immunogenesis (CD40 rs4813003 and FCGR2A rs1801274, which are critical in regulating B-cell immune response, and CASP3 rs113420705, a gene associated with apoptosis, which is extremely important in viral infection).