Identification of a cystic fibrosis mutation W19X in Tunisia.

Cystic fibrosis (CF) is a common and serious condition with autosomal recessive inheritance. It is caused by mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR). The frequencies of mutations vary according to the ethnic origin of populations. We describe in this study a patient with cystic fibrosis. She was homozygous for a new nonsense mutation identified for the first time in Tunisia: W19X, which expected to cause significant morbidity. This mutation appears to be specific to Tunisian population, although, it has identified only in CF Tunisian patients. The information provided by our study contributes to defining the molecular spectrum of CF in Tunisia, to improve genetic testing and prenatal diagnosis.