Independent Contribution of Common CFTR Variants to Chronic Pancreatitis

Objective: We have assessed whether CFTR gene has a major impact on chronic pancreatitis (CP) pathogenesis than that provided by the CFTR mutations. For this aim, we have evaluated clinical parameters, CFTR mutations, and 3 potential regulatory CFTR variants (coding single-nucleotide polymorphisms): c.1540A>G, c.2694T>G, and c.4521G>A. Methods: CFTR gene analysis was performed in a cohort of 136 CP patients and 93 controls from Spanish population using current scanning techniques (single-strand conformation polymorphism/heteroduplex, denaturing gradient gel electrophoresis, and denaturing high-performance liquid chromatography) and direct sequencing. Results: A higher frequency of CFTR mutations were observed in patients (39%) than in controls (15%; P <= 0.001), differences being mostly attributable to the prevalence of the cystic fibrosis (CF)-causing mutations (P = 0.009). The analysis of variants has shown statistically significant differences between patients and controls for c.4521G>A (P-corrected = 0.036). Furthermore, the multi-marker analysis revealed that the 1540A; 2694G; 4521A (AGA) haplotype was more prevalent in CP than controls (P-corrected = 0.042). Remarkably, this association was unrelated to CF-causing mutations (P = 0.006). Conclusions: Our results corroborate the higher susceptibility of CF carriers to CP and, furthermore, suggest that the AGA haplotype could contribute to an increased risk in the development of CP irrespective of other CF-causing mutations.