CFTR and congenital bilateral aplasia of vas deferens from CFTR mutation: But given to relatively low positive rate (1.90% in our study, no CFTR CNVs found in other Chinese studies (Wang et al., 2020; Yuan et al., 2019) and the conditions for detecting CNVs in previous studies (Hantash et al., 2006; Ratbi et al., 2007; Taulan et al., 2007), we recommended that CNV screening should be performed in CBAVD patients with one/no mutation.