67 unrelated cystic fibrosis (CF) patients were screened for some of the most common mutations of the CFTR gene. This analysis resulted in the identification of 34.6% of all CF alleles. The most common mutation is delta F508 (28.4%). Two other mutations account for a further 6.7% of the alleles (R347H: 3.0%; N1303K: 3.7%). 1677delTA, G542X, G551D, S549N/I, R553X, L558S, R334W, and R297Q were not detected.