Specifically, the four-locus model differs between MDD (TIMELESS rs4630333, CSNK1E rs135745, BHLHB2 rs2137947, CSNK1E rs2075984) and BD (TIMELESS rs4630333, CSNK1E rs135745, PER3 rs228669, CLOCK rs12649507), supporting the clinical observation of different circadian characteristics in two disorders. This evidence concerns the gene CSNK1E and Behcet disease.