Clinical Course of a Child With Cystic Fibrosis and the Genotype F508del/CFTRdup1_11: A Case Report.

Cystic fibrosis (CF) is a hereditary disease with great genetic complexity as not all mutations are disease-causing and genotype doesn't always predict phenotype. This case involves a child with CF and genotype F508del/CFTRdup1_11. The CFTRdup1_11 duplication was not reported previously, and genetic counseling was based on reports describing the clinical course of people carrying smaller duplications of the same area combined with F508del. The predicted clinical presentation was CF with pancreatic insufficiency. However, the case presented has so far shown no clinical symptoms and has borderline sweat chloride concentrations.