A defect in the CFTR gene causes cystic fibrosis (CF). This gene makes a protein that controls the movement of salt and water in and out of your body's cells. In people who have CF, the gene makes a protein that doesn't work well. This causes thick, sticky mucus and very salty sweat.
Research suggests that the CFTR protein also affects the body in other ways. This may help explain other symptoms and complications of CF.
More than a thousand known defects can affect the CFTR gene. The type of defect you or your child has may affect the severity of CF. Other genes also may play a role in the severity of the disease.
Every person inherits two CFTR genes—one from each parent. Children who inherit a faulty CFTR gene from each parent will have CF.
Children who inherit one faulty CFTR gene and one normal CFTR gene are "CF carriers." CF carriers usually have no symptoms of CF and live normal lives. However, they can pass the faulty CFTR gene to their children.
The image below shows how two parents who are both CF carriers can pass the faulty CFTR gene to their children.
Clinical trials are research studies that explore whether a medical strategy, treatment, or device is safe and effective for humans. To find clinical trials that are currently underway for Cystic Fibrosis, visit www.clinicaltrials.gov.
Visit Children and Clinical Studies to hear experts, parents, and children talk about their experiences with clinical research.
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