Serum total cholesterol elevation may be in part due to the enhanced cholesterol biosynthesis via up- regulation of the HMG-CoA reductase enzyme [67, 68] as well as due to a relative reduction of hepatic cholesterol elimination via down-regulation of the cholesterol 7α-hydroxylase (CYP7A1) enzyme in CKD animals [69, 70]. This evidence concerns the gene CYP7A1 and chronic kidney disease.