Endocrinol Metab.  2011 Sep;26(3):225-231. 10.3803/EnM.2011.26.3.225.

Androgen Receptor Gene CAG Repeat Polymorphism and Effect of Testosterone Therapy in Hypogonadal Men in Korea

• Kim MJ
• Kim JT
• Cho SW
• Kim SW
• Shin CS
• Park KS
• Kim SY

• KMID: 2169173
• DOI: http://doi.org/10.3803/EnM.2011.26.3.225

Abstract

BACKGROUND
As the number of CAG repeats in the androgen receptor (AR) gene increases, transcriptional activities decrease and the effects of testosterone decline. In this study, we evaluated the importance of the CAG repeat polymorphism in regard to the effect/safety of testosterone therapy in hypogonadal Korean men.
METHODS
The number of CAG repeats was determined in 42 hypogonadal men who underwent testosterone therapy for more than 24 months between December 1999 and August 2007. Body mass index, lean body mass, body fat, bone mineral density, type I collagen N-telopeptide (NTx), osteocalcin, lipid profile, hematocrit and PSA levels prior to and after 24 months of testosterone therapy were identified in our medical record review.
RESULTS
Twenty-four months of testosterone therapy increased lean body mass, hematocrit, and PSA levels and reduced body fat, NTx, and HDL cholesterol levels. The mean number of CAG repeats in the AR gene was 23 +/- 3 (range, 15-29) in hypogonadal Korean men. The number of CAG repeats was not found to be associated with changes in lean body mass, body fat, NTx, HDL cholesterol, hematocrit, or PSA levels during testosterone therapy.
CONCLUSIONS
No association between the number of CAG repeats in the AR gene and the effect/safety of testosterone therapy was detected in hypogonadal Korean men.

Keyword

Androgen receptor; Hypogonadism; Testosterone

MeSH Terms

Adipose Tissue
Body Mass Index
Bone Density
Cholesterol, HDL
Collagen Type I
Hematocrit
Humans
Hypogonadism
Korea
Male
Medical Records
Osteocalcin
Peptides
Receptors, Androgen
Testosterone
Cholesterol, HDL
Collagen Type I
Osteocalcin
Peptides
Receptors, Androgen
Testosterone

Figure

• 

  Fig. 1 The changes in parameters between 4 quartiles according to the number of CAG repeats.

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