The transcription of the three genes of the tauABC operon, which encodes the ABC-transporter for the sulphur-containing amino acid taurine, whose concentration is high in CF patients' sputum [37], and of four genes encoding taurine dioxygenases (tauD, BCAM1121, BCAM1122, BCAM1123), required for the reduction of taurine into sulfite, was found to be up-regulated in IST4113 (Supplementary Table S1; Fig. 5). Here, ABCG2 is linked to cystic fibrosis.