CCND1 and Azoospermia: Some target genes of the downregulated miRNAs, such as ACVR2A, CCND1, CCNE2, HMGA2, BMI1, NR2C2 and BCL2, have been associated with gonadal development, and germ cell maintenance through different pathways which could be relevant to the molecular mechanisms affected in KS patients with azoospermia.