Atherosclerotic cardiovascular disease and gout through a ‘crystal lens’. We thank Prof. Zhou for the images of urate crystals (Molloy R.G.E., Sun W., Chen J., Zhou W. Structure and cleavage of monosodium urate monohydrate crystals. Chemical Communications, 2019, 5). Transmission electron micrograph (courtesy of Satu Lehti and Katariina Öörni, Helsinki, Finland) of cholesterol crystals is from an endarterectomized human carotid atherosclerotic lesion (Helsinki Carotid Endarterectomy Study 2, HeCES2). The micrograph was taken at the Electron Microscopy Unit, Institute of Biotechnology, University of Helsinki, Finland.