Mutation and new polymorphisms insight in introns 11 to 14a of CFTR gene of northern Iranian cystic fibrosis patients

Background: Cystic fibrosis (CF) is the most common autosomal recessive disease in Caucasians, caused by mutation in cystic fibrosis transmembrane conductance regulator (CFTR). The type and distribution of mutations vary widely between different countries and ethnic groups. We therefore aimed to perform a comprehensive analysis of the CFTR gene in northern Iranian CF patients.

Methods: Forty northern Iranian CF patients were analyzed for mutations in introns 11 to 14a of their CFTR genes, using sequencing and reverse dot blot methods. Five normal subjects were also analyzed as normal control.

Results: One mutation and seven polymorphisms were identified. Of the eighty alleles studied, c.2043delG in exon 13 represented 12.5% of mutant alleles and was associated with two distinct haplotypes. rs1042077T>G, rs4148712delAT, rs4148711T>A and rs3808183 T>C with frequencies varying between 29.2% and 6.9% for the least common allele, as well as three new polymorphisms c.1680-224C>A (11.1%), c.2491-275T>G (14.1%) and c.2491-274C>G (35.9%) were detected.

Conclusion: These findings suggest a founder effect for c.2043delG in the Middle East and will assist in genetic counseling, prenatal diagnosis and future screening of CF in Iran.