Ezetimibe, a selective cholesterol absorption inhibitor blocking Niemann-Pick C1 like-1 (NPC1L1) protein, is effective in sitosterolemia caused by ABCG5/ABCG8 mutations but Caamano et al. reported no association between ABCG8: rs11887534 polymorphism and lipid response (including HDL changes) to treatment with ezetimibe [36]. The gene discussed is ABCG5; the disease is sitosterolemia.