CYSTIC FIBROSIS
            
             According to old northern European folklore, a child that tasted salty when kissed upon the forehead was bewitched and would soon die. Today we know the reason -the genetic disease, cystic fibrosis or CF. It is a chronic, progressive disease and the most common, fatal inherited disorder in the United States.
             About 30,000 Americans suffer from cystic fibrosis, and 2500 babies are born in the U.S. with the disease each year. While all races and ethnic groups may suffer from the disease, it occurs most often in whites whose ancestors came from northern Europe. About 1 in every 20 Americans is an unaffected carrier of the disease because they have one abnormal "CF gene".
             Patients with CF produce a thick, sticky mucus; much thicker than a healthy person. The buildup of this mucus clogs ducts and body tubes, leading to chronic tissue inflammation and the replacement of injured cells with scar tissue which blocks the airways of the lungs and ducts in the pancreas and liver. In the lungs, this mucus impairs breathing and causes chronic bacterial infections. Lung disease is the main cause of death from cystic fibrosis. Occlusion of ducts in the pancreas prevents digestive enzymes produced by the pancreas from reaching the intestines where they are required for proper digestion. Cirrhosis of the liver and male infertility are also associated with the disease.
             Until recently, most of the information known about cystic fibrosis was gained from observation. In 1938, Dorothy H. Anderson of Columbia University, provided the first descriptions of body changes produced by CF. From autopsies performed on infants and children, she described destruction of the lungs and pancreas. A decade later, physicians had connected the clogged ducts and passageways to the body's inability to digest nutrients and respiratory failure.
             By 1946, studies about family patterns of disease inheritance led researchers to...