Purpose: The FSHB gene -211G/T polymorphism has been reported to modulate gene expression and to cause inter-individual differences in FSH serum levels in men. This study was undertaken to assess the functional relevance of this polymorphism on gonadotropin and total testosterone serum levels and sperm parameters in men from Eastern Sicily (Italy).
Methods: To accomplish this, 200 men with abnormal conventional sperm parameters or normozoospermia (according to the parameters of WHO 2010) were genotyped by TaqMan Assay.
Results: The frequency of FSHB -211 T allele was significantly higher (p < 0.005) in patients with altered conventional sperm parameters (18.9% of chromosomes) compared to that observed in men with normozoospermia (10.9% of chromosomes). Decreasing serum levels of FSH and LH were observed across the three FSHB -211 genotype subgroups (p < 0.001 and p < 0.05, respectively). In addition, the FSHB -211G/T polymorphism showed a total testosterone downward trend that became more evident in men with the TT genotype compared to subjects with the GG genotype (p = 0.05). Furthermore, we found a trend towards decreased sperm concentration, total sperm count, sperm forward motility and testicular volume in men with GT and TT genotypes.
Conclusions: These findings showed that the FSHB -211 G/T polymorphism modulates male gonadal function with a clear influence on hormonal levels and sperm parameters.
Capsule: The present study was undertaken to evaluate the distribution of the FSHB -211 G/T in men with normal or abnormal sperm parameters from Southern Italy to assess its functional relevance on the serum levels of reproductive hormones and on sperm parameters in men.
Keywords: FSH (follicle-stimulating hormone); Gonadotropins; Single nucleotide polymorphism; Sperm count.