AR and male infertility: Nowadays, increasing numbers of researchers have focused their attention on the relationship between genetic polymorphisms and male infertility, including methylene-tetrahydrofolate reductase (MTHFR) [4, 5], deleted in azoospermia like gene (DAZL) [6, 7], androgen receptor gene (AR) [8], glutathione S-transferase genes (GSTM1, GSTT1, GSTP1) [9–11] and follicle stimulating hormone receptor gene (FSHR, OMIM:136,435) [12–14], or FSH beta subunit (FSHB,OMIM:136,530) [15].