Insulin is needed to regulate sugar levels in the blood. while every cell in the body contains genes for the production of insulin, it is only produced by a specialized subset of cells in the pancreas. therefore:

Therefore; there should be mechanism of gene regulation that promote insulin expression in the specialized pancreatic cells and prevent insulin expression in all other cells. Regulation of gene expression includes a wide range of mechanism that are used by cells to increase or decrease the production of specific gene products and is informally termed gene regulation.