CFTR and cystic fibrosis: Considering that in our patient the 3041-15T>G change is combined with the L138ins variant (c.413_415dupTAC, rs397508679, p.Leu138dup), which is a mild pathogenic variant and is classified as a class IV-V mutation in the CFTR gene by the pathogenicity mechanism, the girl does not have pronounced manifestations of CF and is under dynamic observation.