▲ Genetically altered bacteria can now produce in abundance such valuable drugs as insulin, human growth hormone, and a vaccine for hepatitis B.

Take insulin, for example. One of the early practical results of recombinant-DNA technology was to track down the gene (located on chromosome 11) for human insulin and then splice copies of it into ordinary E. coli bacteria. These altered bacteria can produce large quantities of insulin with the exact structure of the human insulin molecule. Amazing!

It took several years, however, for this technology to move out of the laboratory, through clinical trials, past the U.S. FDA drug approval process, and finally into full-scale production and wide availability. The availability of this insulin does not mean that a cure for diabetes has been found, as any diabetic will tell you. In fact, while the product “may have certain advantages for people newly treated with insulin or allergic to the usual beef/​pork insulin [it] is not necessary for the majority of people taking the conventional preparations,” according to Dr. Christopher D. Saudek, director of the Johns Hopkins Diabetes Center.