Contribution of common CFTR variants (M470V, T854, and Q1463) to cystic fibrosis in Tunisia: haplotype analysis.

BACKGROUND & OBJECTIVES Cystic fibrosis (CF) is caused by mutations in the gene encoding the CF transmembrane regulator (CFTR) protein, a chloride channel located in the epithelial cell membrane. Over than 2,000 CFTR mutations have been identified, which contribute to the variety of clinical phenotypes of CF. We performed a case-control study to determine p.Met470Val (M470V), p.Thr854= (T854) and p.Gln1463= (Q1463) polymorphisms frequencies in CF patients and healthy controls and to elaborate haplotype based on these SNPs. METHODS The genotyping of M470V (exon 10), T854 (exon 14a), and Q1463 (exon 24) variants were identified using polymorphism restriction fragment length polymorphism (RFLP). RESULTS & CONCLUSION Statistical difference was noted in the genotype distribution of two markers, M470V and T854, between CF and control groups. However, the Q1463 polymorphism is not identified in two studied groups. Three haplotypes were found in CF patients and controls. An exclusive association between the ancestral haplotype 1-1-2 and p.Phe508del (F508del) mutation was shown. In Tunisia, this is the first work to be interested in the analysis of M470V, T854 and Q1463 polymorphisms and haplotypes associated with the most common mutation, F508del, in the Tunisian population and worldwide.