Clinical and Genetic Features in Patients with Cystic Fibrosis in Southwestern Iran

Objective: Cystic fibrosis (CF) is a common autosomal recessive genetic disease caused by a mutation in the CF transmembrane conductance regulatory (CFTR) gene. This study attempted to identify the most common CFTR mutations and any correlations between certain mutations and the clinical presentation of the disease in CF patients in southwestern Iran.
Methods: Twenty nine common CFTR gene mutations were examined in 45 CF patients.
Findings: Chronic cough, intestinal obstruction, dehydration, heat exhaustion and steatorrhea were the most common early clinical symptoms among our patients. The most common mutation was ∆F508, with an allele frequency of 21%. The homozygous ∆F508 mutation was observed in eight patients (18%), and three patients (7%) were ∆F508 carriers. The 2183AA>G mutation was observed in four patients, one of whom was also a ∆F508 carrier. The R1162X mutation was detected in two patients. The G542X, R334W and N1303K mutations were detected each in one patient, the first of whom was also a ∆F508 carrier.
Conclusion: Out of 45 patients, 27 (60%) had none of the CFTR gene mutations we tested for. The most frequent mutations in southwestern Iranian patients with CF should be identified by sequencing the entire CFTR gene in order to optimize the design of a diagnostic kit for common regional mutations.