The transcription-translation feedback loop of clock genes (e.g., <i>BMAL1</i>, <i>CLOCK</i>, <i>PER1/2/3</i>, and <i>CRY1</i>/<i>2</i>) provides a promising novel avenue for deciphering the initiation and progression of CRC. The gene discussed is PER1; the disease is colorectal carcinoma.