What is cystic fibrosis?

Cystic fibrosis (CF) is an inherited disease of the glands that make mucus and sweat. People with CF get a defective gene from both parents. People who have one defective gene from one parent are called carriers. They don't have the disease.

CF is a long-term (chronic) disease that gets worse over time. It is a life-limiting condition. But better treatments have made it possible for people with this disease to live longer lives. Most people with CF live into their late 30s, and many even into their 50s or longer.

CF affects a cell protein called cystic fibrosis transmembrane conductance regulator (CFTR). CFTR controls the flow of water and certain salts in and out of the body's cells. As the movement of salt and water in and out of cells is changed, the mucus that many cells normally make gets thicker. This thicker mucus can affect many organs and body systems including:

• Respiratory. This includes sinuses and lungs.

• Digestive. This includes pancreas, liver, gallbladder, and intestines.

• Reproductive. Both men and women may have reproductive problems.

• Sweat glands. CF makes sweat very salty. When people with CF sweat, they lose large amounts of salt. This upsets their body’s mineral balance and leads to other health problems.

More than 30,000 people in the U.S. have the disease. More than half of those with CF in the U.S. are age 18 or older. In the U.S., CF affects both males and females from all racial and ethnic groups. But it is more common in whites whose families are from northern Europe. It is less common among African Americans, Hispanic Americans, Asian Americans, and American Indians.

About 1 in 30 people in the U.S. is a carrier of the cystic fibrosis gene. They don't have symptoms. Often they don't know that they are carriers.