Yes, it is true. When I was a medical student, I was taught that people who were carriers for the cystic fibrosis gene would not manifest any of the problems of the disease. As time and science move forward this turns out not to be the case.
Cystic Fibrosis is inherited as an autosomal recessive disease; that is, it takes the bad gene from both parents to cause the disease. Carriers have only one copy of the gene which is known as the cystic fibrosis transmembrane conductance regulator (CFTR) protein.
The frequency for carriers varies by race:
White 1 in 3,200
Black 1 in 15,000
Hispanic 1 in 14,000
Asian 1 in 35,000
The disease, cystic fibrosis, affects the sinuses, lungs, pancreas, intestinal tract and other organs. It commonly leads to chronic sinus and lung infections and pancreatic failure.
Recent epidemiologic studies have revealed that carriers have increased risk for some of the same problems. Carriers have a greater tendency for sinus and lung infections. They also have a greater risk to develop bronchiectasis, a chronic infection in the bronchial tubes. The risk for respiratory failure is higher too. In the GI tract pancreatitis and pancreatic cancer are more common in carriers.
To date there is no specific cure for cystic fibrosis, much less the carrier state. But gene therapy is coming close to being a reality. In the meantime, being aware of greater risk as a carrier could help early in the intervention and screening for infections and cancer.