They found three polymorphisms in miR-99b/let-7e/hsa-miR-125a gene cluster derived from the same precursor that influence maturation of their primary transcripts and deltaF508-CFTR mutation can induce an upregulation of miR-99b and miR-125a gene expression, indicating that these miRNAs are important in CF pathogenesis. This evidence concerns the gene CFTR and cystic fibrosis.