The Novel CFTR Haplotype E583G/F508del in CFTR-related Disorder

Background: CFTR-related disorder (CFTR-RD) is a clinical entity associated to complex diagnostic paths and newly upgraded standard of care. In CFTR-RD, CFTR genotyping represents a diagnostic surrogate marker. In case of novel haplotype, the diagnosis could represents an area of concern. We described the molecular evaluation of the rare CFTR variant E583G identified in trans with the F508del in a novel haplotype.

Methods And Results: An adult woman was referred to our pulmonary unit for persistent respiratory symptoms. CFTR Next Generation Sequencing was performed to evaluate full-gene mutational status. The variant identified was evaluated for its pathogenicity integrating clinical evidences with dedicated bioinformatics analyses. Clinical evaluation of patient matched with a mono-organ CFTR-RD diagnosis. Genotyping revealed the novel CFTR haplotype F508del/E583G. Multiple evidences of a deleterious effect of the CFTR E583G rare variant emerged from the bioinformatics analyses performed.

Conclusions: Guidelines for CFTR-RD are available with the purpose of harmonizing clinical and molecular investigations. In such context, the identification of novel CFTR haplotype need to a deeper evaluation with a combination of skills. The novel E583G variant could be considered of clinical interest and overall a CFTR-RD Variants of Varying Clinical Consequences.