Cilia are antenna-like protrusions found on almost every human cell type that are involved in the transmission of various sensations including the sense of smell. Thus, genetic defects disrupting the functional or structural integrity of cilia may result in olfactory dysfunction. Renal ciliopathies are among the most abundant representatives of these genetic disorders. Here, we provide the first systematic evaluation of olfaction in children and adolescents displaying various kidney diseases including Bardet-Biedl syndrome, nephronophthisis-related ciliopathies and polycystic kidney diseases. We demonstrate that a reduced sense of smell is part of the clinical spectrum of different renal disorders and differs significantly depending on the genetic background. (By Dr. Jens König, )