A list of 15 known clock genes from the primary (Arntl, Clock, Npas2, Per1, Per2, Per3, Cry1, Cry2), secondary (Nrd1d1, Nr1d2, Rora, Rorb, Rorc), and accessory TTFL loops (Nfil3, Dbp) (Fig. 1A) were selected to investigate the effect of diabetes on their rhythmic expression. The gene discussed is DBP; the disease is diabetes mellitus.