Familial advanced sleep-phase syndrome (FASPS) is an autosomal dominant disorder caused by a missense mutation in the CSNK1D gene, which encodes for the Casein Kinase Iδ (CK1δ) [150], a serine/threonine kinase which phosphorylates several important target proteins in order to regulate the cell cycle, cell differentiation, proliferation, and the circadian clock [151,152]. The gene discussed is CSNK1D; the disease is advanced sleep phase syndrome.