Stearoyl-CoA desaturase (SCD) introduces a double bond between C9 and C10, converting saturated fatty acids (C16:0 and C18:0) to monounsaturated fatty acids (C16:1n-7 and C18:1n-9)[38], which are key substrates for biosynthesis of triglycerides, phospholipids, cholesterol esters, etc. Furthermore, the expression of scd genes and the activity of SCD were found to be related to several metabolic diseases[38,42]. This evidence concerns the gene SCD and metabolic disease.