A significant gene–gene interaction was found in the 19 variants, and the best interactive model for carotid atherosclerosis was interaction among IL1A rs1609682, ITGA2 rs1991013 and HABP2 rs7923349, which scored 10/10 for the cross-validation consistency and 10 for sign test (p = 0.001, Table 3). The gene discussed is ITGA2; the disease is carotid atherosclerosis.