Since both osteogenic and chondrogenic ossification (or bone formation) are present in CAVD (Rajamannan et al. 2011; Mohler et al. 2001), reduced SOX9 promotes aortic valve calcification (Peacock et al. 2010; Lincoln et al. 2007), whereas SOX9 overexpression induces chondrogenesis, which is regulated by the Wnt/β-catenin signaling (Fang et al. 2014). This evidence concerns the gene SOX9 and congenital bilateral aplasia of vas deferens from CFTR mutation.