Figure 8. Reference numbering of the androgen receptor (AR) of protein. The numbering of the amino acid residues is according to National Center for Biotechnology Information (NCBI) reference sequence number NM_000044.3, which refers to a gene size of 187,246 nucleotides and an AR protein of 920 amino acid residues with a polyglutamine tract of 23 and a polyglycine tract of 23 (110). Amino acid numbering +2 between 78 and 449; Amino acid numbering +1 between 472 and 919. In addition, a number of splice variants of the AR have been identified in prostate cancer cell lines and patient samples. These splice variants lack most or all of the LBD but retain a functional DBD and NTD with unique C-terminal sequences derived from cryptic exons (CE) (e.g., AR-v7).