To induce atherosclerosis in Endo-Hdac9KO mice and their littermate controls, we administered a single dose of proprotein convertase subtilisin/kexin type 9–encoding (PCSK9-encoding) recombinant adeno-associated viral vector at 7 weeks of age and then fed mice a high-fat diet from 8 weeks of age for 16 weeks. Here, PCSK9 is linked to atherosclerosis.