To assess whether the attenuation of myocardial fibrosis and calcification progression by miR–129-5p may be explained by differences in expression of SOX9 and ASPN in CF, we employed lineage tracing of CF of the transcription factor 21 (Tcf21) lineage in mice (Tcf21MCM/+;R26EGFP mice). This evidence concerns the gene TCF21 and cystic fibrosis.