Human insulin for the treatment of diabetes, one of the first genetically engineered products to become commercially available, was marketed in 1982. Since then, biotechnologists have been working to develop new ways for health care professionals to detect and fight disease.
· Detecting and Treating Hereditary Diseases
Many diseases, including some types of anemia, cystic fibrosis, Huntington's disease, and some blood disorders, are the result of a defective gene that parents pass to their children.
Biotechnologists are working to identify and locate where defects occur in genes that are related to hereditary diseases. Once the correct genetic code is known, health care professionals hope, in the future, to be able to replace the missing or defective genes to make the individual healthy.
Currently, prospective parents can be screened for such genetic defects and counseled about the likelihood of their children being affected.
Fetuses are being screened for genetic disorders before they are born and, again, genetic counselors play an important role in informing parents concerning the test results. Genetic counselors prepare parents for the birth and early medical treatment of a child with a genetic disorder.
· Heart Disease
Heart attacks occur when a blood clot enters one of the coronary arteries and cuts off blood flow to a portion of the heart. If the artery is not reopened quickly, severe damage to the heart can occur.
Doctors can now prescribe a genetically engineered drug called tissue plasminogen activator (TPA) that travels to the blood clot and breaks it up within minutes, restoring blood flow to the heart and lessening the chance of permanent damage.
Medical professionals are using biotechnology to treat cancer in several ways. Genetically engineered proteins called lymphokines seem to work with the body's immune system to attack cancer cells and growth inhibitor proteins seem to slow the reproduction of cancer cells. Highly specific and purified antibodies can be loaded with poisons that locate and destroy cancer cells.
Genetic engineering has produced several substances that show promise in the treatment of AIDS. These substances stimulate the body's own immune system to fight the disease.
· Other Diseases
Many other diseases can be treated with genetically engineered products. Doctors can use a genetically engineered vaccine to treat human hepatitis B or a growth hormone to help children with dwarfism.
Other treatments developed through genetic engineering techniques include a protein to control blood clotting in hemophiliacs, a hormone that stimulates red blood cell production to fight anemia, and antibodies that discourage organ rejection by transplant patients.