Polymorphisms in gonadotropin and gonadotropin receptor genes as markers of ovarian reserve and response in in vitro fertilization
Some genetic polymorphisms are associated with ovarian response to gonadotropin administration and exhibit potential for a pharmacogenetic approach in ovarian stimulation. In contrast, ovarian reserve seems to be independent of gonadotropin variants.
Antonio La Marca, M.D., Ph.D., Giovanna Sighinolfi, M.D., Cindy Argento, M.D., Valentina Grisendi, M.D., Livio Casarini, M.D., Annibale Volpe, M.D., Manuela Simoni, M.D.
Volume 99, Issue 4, Pages 970-978.e1, 15 March 2013
Since gonadotropins are fundamental hormones that control ovarian activity, genetic polymorphisms may alter gonadal responsiveness to glycoproteins hence being important regulators of hormonal activity at target level. The establishment of the pool of primordial follicles take place during fetal life and is mainly under genetic control. Consequently single nucleotide polymorphisms (SNPs) in gonadotropins and their receptors do not seem to be associated with any significant modification in the endowment of non-growing follicles in the ovary. Indeed, the age at menopause, a biological characteristic strongly related to ovarian reserve, as well as markers of functional ovarian reserve as AMH and AFC are not different in women with different genetic variants. Conversely, some polymorphisms in FSH receptor (FSHR) seem to be associated with modifications in ovarian activity. In particular, studies suggest that Ser680 genotype for FSHR is a factor of relative resistance to FSH stimulation resulting in slightly higher FSH serum levels, thus leading to prolonged duration of the menstrual cycle. Moreover some FSHR gene polymorphisms show a positive association with ovarian response to exogenous gonadotropin administration, hence exhibiting some potential for a pharmacogenetic estimation of the FSH dosage in controlled ovarian stimulation. The study of SNPs of the FSHR gene, is an interesting field of research that could provide us with new information about the way each woman responds to exogenous gonadotrophin administration during ovulation induction.