Androgen Receptor-Coding Gene Analysis

As stated above the androgen receptor-coding gene is located in band Xq11-q12 on the long arm of the (X) chromosome. This portion of the X chromosome is about 90kb and contains 8 exons that code 919 amino acids with a mass of approximately 110kDa. These many amino acids determine the structure of the transcription factor protein involved in steroid-hormone activation. The androgen receptor has several functional domains, which are inconsistently classified among various literature. In general the functional domains include an N-terminal domain (NTD), a DNA-binding domain (DBD), a short hinge region, and a COOH-terminal domain that contains the ligand-binding domain (LBD) (Dehm & Tindall, 2007). The LBD is where the ligand androgen binds to
Nine to ten weeks into the gestation period, the SRY gene begins the specialization of the Leydig cells. More specifically, differentiating Sertoli cells assemble into testis cords and stimulate the production of sex-specific germ cells, Leydig cells (Kashimada & Koopman, 2010). These cells produce of testosterone, which is primarily involved in the androgen receptor LBD. With this androgen present the Wolffian ducts develop into the vas deferens, epididymis, and seminal vesicles. The cytochrome P450 5α-reductase enzyme catalyzes the conversion of testosterone to dihydrotestosterone (Longergan & Tindall, 2011). Dihydrotestosterone is an androgen that influences the growth of the prostate and external genitalia. Once testosterone and dihydrotestosterone bind with the hormone binding pocked located in the androgen receptor a conformational change occurs where helices 3, 4, and 12 form the protein-protein interaction surface used by nuclear receptors (Longergan & Tindall, 2011). In AIS functional androgen receptors are not present. This causes the Wolffian ducts to decay and the eventual failure of the prostate to develop, which result in the development of external female genitalia (Blaschko et al.,