However, the fact that clock genes independently affect diabetes [75], obesity [75], and hypertension [76,77], which are risk factors for CKD and heart failure, and that clock genes play different roles in different cells such as immune cells [78,79], vascular smooth muscle cells [80], fibroblasts [81], and adipocytes [82], is a major barrier to analyzing the relationship between CKD, heart failure, and clock genes using molecular biology. The gene discussed is CLOCK; the disease is diabetes mellitus.