Serum levels of testosterone and gonadotrophins with respect to smoking status and genetic polymorphism of GSTT1

Abstract

Objectives It is reported that parental exposure to toxicants can influence offspring sex ratio at birth. Studies have reported that several chemicals found in cigarette smoke are substrates of glutathione S-transferase T1 (GSTT1, a member of GSTtheta). To determine the effect of cigarette smoke on serum levels of testosterone and gonadotrophins of smokers and possible association of these hormones levels with GSTT1 polymorphism, the present study was done. Methods Our study was conducted on 181 (40 smokers, 141 non-smokers) male subjects. Genomic DNA was extracted from peripheral blood. The GSTT1 genotyping was performed using PCR-based method. All measurements for testosterone, follicle stimulating hormone (FSH), and luteinizing hormone (LH) were done in one laboratory. Results In smoker subjects the mean +/- sd of serum testosterone, FSH, and LH were 4.64 +/- 1.63 ng/ml, 2.72 +/- 1.17 IU/l, and 3.03 +/- 1.04 IU/l, respectively. In non-smoker subjects the mean +/- sd of serum testosterone, FSH, and LH were 4.49 +/- 1.24 ng/ml, 2.89 +/- 1.26 IU/l, and 3.07 +/- 1.28 IU/l, respectively. There was no significant difference between smokers and non-smokers for serum testosterone (t = 0.622, df = 179, P = 0.535), FSH (t = -0.757, df = 179, P = 0.450), and LH (t = -0.179, df = 179, P = 0.858). Also there was no significant difference between smokers and non-smokers in either GSTT1 null or positive genotypes for levels of testosterone, FSH, and LH. Conclusion Based on present data,…