AR and osteoporosis: Regarding the androgen receptor, a polymorphic (AGC)n repeat trinucleotide polymorphism, which has been identified in the first exon of the coding sequence, has been associated with reduced transcriptional activity of the receptor, thereby leading to a reduced bone mass in women with high levels of sex hormone-binding globulin (SHBG) and with an increased risk of osteoporosis fractures [147].