The cloning of the insulin gene

Human Insulin and Recombinant DNA Technology

Diabetes mellitus is a heterogeneous group of chronic diss that manifest as high levels of blood glucose , and which result from impaired insulin action or production (Power , 2005 National Diabetes Information Clearinghouse , n .d . As of 2005 , more than 20 million Americans of all ages (7 of the American population ) suffer from diabetes , spending more than 100 billion to stave off disease morbidity and mortality (NIDDK . Apart from the economic burden , the physical impact of this disease is immense . In 2002 , diabetes was the sixth

leading cause of death in the United States (NIDDK . Those who do survive are bound to suffer from systemic complications , which involve the heart , brain , eyes , kidneys , and the limbs , not to mention the ever present danger of falling into coma with uncontrolled diabetes (Clark 2004

Insulin remains the mainstay of treatment for diabetes , and its discovery in 1921 is considered as one of the most dramatic , most important events in the history of medicine - a crucial turning point in fact . Prior to this , diabetes , especially insulin-dependent (type 1 diabetes mellitus , was considered a fatal dis (Davis Granner 2001 . Since 1922 , advances in technology have allowed humans to produce insulin , first from animal sources (bovine and porcine insulin ) using crude extraction techniques , then later , through recombinant DNA technology , from humans , and as a result , significantly reduce mortality from diabetes

This briefly discusses the history of insulin , from the time of its discovery in the early 1920s , to the production of insulin through extraction techniques , to the 1980s when the first recombinant human insulin was introduced in the market . The physiology of insulin production and action in the human body is reviewed , and later correlated with diabetes mellitus . The final part of this focuses on present trends in the use of recombinant human insulin as part of the armamentarium for the treatment of diabetes mellitus

Hormones are chemicals in the human body , secreted by special cells or organs into the bloodstream , that act on distant organs to regulate growth , development , and function (Clark . Hormones , in essence , act to stabilize the internal body situation in the face of fluctuations in the physical environment , and amounts of nutrients , minerals , and water available for expenditure at any given time (Genuth , 2004a . This process of maintaining a constant physical and chemical milieu is aptly termed homeostasis , and both the quantity and quality of hormones present , as well as their relative proportion to other body chemicals are crucial in maintaining this state of dynamic equilibrium , and , in effect , health (Genuth

Insulin is a hormone produced by the pancreas that functions to regulate the amount of glucose , the body 's primary source of energy , within the human body (Power . Insulin is a polypeptide (i .e . a complex protein hormone derived specifically from the beta cells of the pancreatic islets (Genuth , 2004b . It is initially produced from a complex precursor molecule , termed preproinsulin , composed of four sequential peptides , referred to as the N-terminal signal peptide...