AR CAG repeat length is not associated with serum gonadal steroids and lipid levels in healthy men

Abstract

Cardiovascular risk factors seem to be affected by androgens, which exert their action through the androgen receptor (AR). Androgenic action correlates inversely with a polymorphic CAG repeat region in the AR gene encoding for glutamine residues the length of which appears to influence high density lipoprotein (HDL) cholesterol levels. The aim of the study was to investigate the possible association between AR gene polymorphism and serum sex steroids and lipids. 170 healthy males, aged 22-59 years (mean 42 years), were included in the study. Anthropometrical as well as sociometrical parameters were recorded. Body fat content (BFC) (% fat mass) was measured by bioelectrical impedance. Serum lipids and total and free testosterone (T) and estradiol (E(2)) levels were measured in each subject. AR gene CAG repeats length was determined. No significant correlation was found between the length of AR gene polyglutamine tract and the levels of gonadal steroids (total and free T, total and free E(2)) or to the lipid levels (Triglycerides, total, HDL and LDL cholesterol). In addition, serum lipid levels were not significantly different in the lower compared to higher half of CAG repeats length distribution. On multiple regression analysis BFC was found to predict HDL-cholesterol and triglycerides were found to show, respectively, significant negative and positive correlation with body fat content. In conclusion, AR gene polymorphism may not predict sex steroid levels in healthy males. Possible impact of CAG repeats length on lipids profile has not been established.