Several CF transcriptomics studies have employed microarrays to measure differences in global gene expression caused by the F508del mutation in isogenic bronchial cells [16] (in this case the CFTR genotype was F508del/W1282X), primary cultures of tracheal and bronchial cells [17], native nasal epithelial and bronchial cells [18,19] and immortalized foetal tracheal cell lines [20]. The gene discussed is CFTR; the disease is cystic fibrosis.