Male infertility: the role of FSH gene polymorphisms and its FSHR receptor

The FSH hormone plays a fundamental role in the induction and maintenance of spermatogenesis and its action in reproductive physiology is modulated by genetic variants that affect the levels of the circulating hormone (FSH) or the functionality of its receptor (FSHR).

Gene mutations that alter the functional domain of the beta subunit (FSHB) or significantly reduce its relative quantity, severely impact the spermatogenesis of carriers.

The detection of the polymorphism in the FSHB gene (-211G> T) encoding the beta subunit of the hormone and associated with reduced serum FSH levels, testicular volume and reduced sperm count has stimulated intense clinical interest. and experimental.

Numerous prospective and retrospective clinical studies undertaken in recent years have confirmed that the genetic variants -211 GT and TT, by modulating the transcriptional capacity of the promoter region of the FSHB gene, determine a significant quantitative reduction of the hormone (more pronounced in the homozygous TT combination).

A synergistic effect in the reduction of reproductive physiological parameters seems, moreover, accentuated by the contextual presence in the patient of the genetic polymorphisms -29 AA and N680S of the gene encoding the FSH receptor (FSHR).

A prospective and longitudinal multicentre pharmacogenetic study recently demonstrated that in patients with a clinical history of idiopathic infertility, serum FSH levels <8UI and sperm fragmentation index

(DFI)> 15%, treatment with recombinant FSH for at least 3 months significantly improves the sperm fragmentation index and reproductive competence in subjects carrying a homozygous allelic combination (Asn / Asn) at codon 680 of the FSHR and homozygosity for the GG genotype of the FSHB variant - (211G> T)

These results encourage the implementation of the study of genetic polymorphisms for the FSH receptor (FSHR) and FSHB in patients with a history of infertility or candidates for assisted reproductive technologies.

Analytical information about the test

Genetic tests for FSHR and FSHB are carried out in our center following rigorous quality controls, using analytical protocols validated by specialist literature.

Sampling: 2-5 ml of EDTA blood

Time required for diagnostic response: 10 days

Bibliography

Grebb RR 2005: J Clinic Endocr and Metabolism: 90 (8) 4866-4872

Grigorova M et al 2008: Human Reproduction: 23; 2160-66