Causes of Cystic Fibrosis

Cystic fibrosis is a disease of the mucus and sweat glands in the body. The disease mostly affects the lungs, liver, pancreas, intestines and sex organs.

In a person who does not suffer from cystic fibrosis, mucus is watery and will keep the linings of specific organs moist to prevent them from drying out or getting infected. When a person has cystic fibrosis this mucus becomes sticky and very thick.

Thick mucus can build up in the lungs and block the airways. Bacteria will grow in the thick mucus and cause repeated lung infections. Chronic lung infections will cause irreversible damage to the tissue of the lungs.

The mucus can also block the tubes or ducts that are found in the pancreas. This will prevent digestive enzymes from leaving the pancreas and getting to the small intestine. These digestive enzymes are important because they break down the food that is eaten into much needed fats and protein. Malnutrition can be a problem for those with cystic fibrosis because the food will leave the body unused. Some people with cystic fibrosis will have complications with a swollen belly and abdominal pain.

The symptoms of cystic fibrosis and the severity of these symptoms will vary from person to person. Some people will have a continuing battle with lung and digestive problems while others will have such mild symptoms that they wont show up until they are into adulthood.

A defect in a gene called the cystic fibrosis transmembrane conductance regulator gene or CFTR, is the causative factor in the development of this condition. This particular gene produces the protein that controls the movement of salt and water in and out of the cells of the body.

The CFTR gene does not work properly in people with cystic fibrosis. Therefore, thick sticky mucus and very salty sweat are the two main features of cystic fibrosis.

Every person inherits two CFTR genes, one from each parent. If one of these genes is abnormal that person will be a carrier of cystic fibrosis. If both genes that are inherited are abnormal the person will have cystic fibrosis.

A person may be a carrier of cystic fibrosis but have no symptoms. They have a 50% chance of passing the defective gene on to their children. If two cystic fibrosis carriers have a baby there is a one in four chance that baby will have cystic fibrosis.

There are approximately 30,000 people in the United States with cystic fibrosis. This disease affects both males and females and people from all racial and ethnic groups. It is estimated that about twelve million people are carriers of the abnormal cystic fibrosis gene. Many of these twelve million people do not know they are carriers.

For those diagnosed with cystic fibrosis it is important that they have ongoing medical management from a team of health care providers that specialize in cystic fibrosis. More research is being done every day to hopefully one day find a cure for this debilitating and deadly disease.

RESOURCES

Genomics: CFTR: The Gene Associated with Cystic Fibrosis

Genetics: CFTR

Stanford University: Mutations in the CFTR Gene

British Medical Journal: The Pathogenic Consequences of a Single Mutated CFTR Gene

MayoClinic: Cystic Fibrosis Causes

National Heart Lung and Blood Institute: What Causes Cystic Fibrosis