A genetic disorder that causes a thick mucus to build up in the respiratory system and in the pancreas, a digestive organ. People with cystic fibrosis are highly susceptible to respiratory infections and are typically malnourished due to the malfunctioning of the pancreas.

One of every 25 babies born in the United States is affected with cystic fibrosis, the most common fatal genetic disease in the nation. The average life expectancy of people with cystic fibrosis is 29 years. Only 10% of people with the disease survive into their 30s. Ninety-five percent of cystic fibrosis deaths are caused by lung complications; the other 5% are due to liver failure.

Most cases of cystic fibrosis are caused by a defective gene that must be carried by both parents to produce a child with cystic fibrosis. It is estimated that one in every 20 Americans carries the defective gene. When two carriers have...