Currently, the following most common genetic causes of male infertility are clearly documented: microdeletions in AZFa, AZFb, and AZFc regions of the AZF locus of the Y chromosome (Kamp et al., 2001; Fernandes et al., 2002, 2006; Krausz et al., 2015; Kim et al., 2017), androgen receptor (AR) mutations, including CAG repeat polymorphism in exon 1 (Xiao et al., 2016), chromosomal abnormalities (Alves et al., 2002; Aston and Conrad, 2013; Madureira et al., 2014), cystic fibrosis gene (CFTR) polymorphism (Vallières and Elborn, 2014; Jiang et al., 2017). Here, CFTR is linked to male infertility.