Abstract
The androgen-androgen receptors (AR) signalling pathway plays a role in skeletal muscle development and it is necessary for the anabolic effect elicited by androgen stimulation. The AR gene contains a GGN and a CAG repeat polymorphism in exon 1, which length is inversely associated with transcriptional activity of the AR. PURPOSE. The aim of this study was to determine if there is an association between AR CAG and GGN tract polymorphisms repeat length, and lean mass in a cohort of 345 healthy subjects.METHODS. Three-hundred forty five subjects (284 men, 61 women; age: 28.8 ± 7.6; 25.4 ± 6.7 years; height: 176.8 ± 5.5; 165.3 ± 5.8 cm; body mass: 78.1 ± 1; 60.6 ± 7.8 kg, men and women, respectively) agreed to participate in this study. Subjects were genotyped by polymerase chain reaction (PCR) to determine the number of AR CAG and GGN repeats, and grouped as carrying repeat lengths of 21 (i.e. long allele) for males CAG; 22 for females CAG; and 23 for both males and females GGN. Whole body lean mass and the lean mass of the extremities were determined by DXA. Differences in lean mass were determined using ANCOVA with 2 factors gender (male, female) and polymorpism (short, long) with height as covariate. RESULTS. The whole body lean mass was 7% greater in the women with a shorter CAG tract polymorphism (42.5 ± 6.1 vs 39.7 ± 6.1 kg, short and long, respectively, P=0.009). This difference was explained by a greater muscle mass in the extremities of the women with the shorter CAG polymorphisms (17.2 ± 3.4 vs 15.9 ± 3.4 kg, short and long, respectively, P=0.055). Neither GGN nor CAG polymorphism was associated with lean whole body or muscle mass in males.CONCLUSION. Women with a shorter androgen receptor CAG repeat polymorphism (22). Neither GGN nor CAG repeat polymorphisms are associated with muscle mass in healthy males. Supported by a grant from Ministerio de Educación y Ciencia, Spain (DEP2006-56076-C06-04/ACTI).
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
