Mice that are genetically engineered to lack both the Cx37 gene (Gja4 −/− ) and a gene that prevents high cholesterol (Apoe −/− ) develop more severe atherosclerosis of the arteries (aortic lesions) than mice that only lack the Apoe gene (Gja4 +/+ Apoe −/− ). This evidence concerns the gene GJA4 and atherosclerosis.