Advanced molecular approaches in male infertility diagnosis

In the recent years a special attention has been given to a major health concern namely to male infertility, defined as the inability to conceive after 12 months of regular unprotected sexual intercourse, taken into account the statistics that highlight that sperm counts have dropped by 50-60% in recent decades. According to the WHO, infertility affects approximately 9% of couples globally, and the male factor is believed to be present in roughly 50% of cases, with exclusive responsibility in 30%. The aim of this manuscript is to present an evidence-based approach for diagnosing male infertility that includes finding new solutions for diagnosis and critical outcomes, retrieving up-to-date studies and existing guidelines. The diverse factors that induce male infertility generated in a vast amount of data that needed to be analysed by a clinician before a decision could be made for each individual. Modern medicine faces numerous obstacles as a result of the massive amount of data generated by the molecular biology discipline. To address complex clinical problems, vast data must be collected, analysed, and used, which can be very challenging. The use of artificial intelligence (AI) methods to create a decision support system can help predict the diagnosis and guide treatment for infertile men, based on analysis of different data as environmental and lifestyle, clinical (sperm count, morphology, hormone testing, karyotype, etc.) and "omics" bigdata. Ultimately, the development of AI algorithms will assist clinicians in formulating diagnosis, making treatment decisions, and predicting outcomes for assisted reproduction techniques.

THE INVOLVEMENT OF VDR PROMOTER METHYLATION, CDX-2 VDR POLYMORPHISM AND VITAMIN D LEVELS IN MALE INFERTILITY

INTRODUCTION

Vitamin D (VD) levels were correlated with different health conditions, including reproductive disorders in males. Vitamin D action is mediated through vitamin D receptor (VDR), which acts as a transcription factor. VDR gene promoter is embedded in a GC-rich island. The VDR gene has been shown to have several polymorphisms that affect the receptor function.

AIM

To examine the relationship between Cdx-2 polymorphism (rs17883968), the methylation status of VDR's promoter and serum levels of 25-hydroxyvitamin D in male infertility.

PATIENTS AND METHODS

A total of 69 infertile men and 37 age-matched controls were enrolled in this study. Vitamin D level assessments were detected using the electrochemiluminescent method. Cdx-2 VDR polymorphism identification was performed by PCR on DNA samples from blood, followed by restriction. Methylation of VDR gene promoter was assessed by qMS-PCR using bisulfite-treated DNA from fresh sperm.

RESULTS

Vitamin D levels was found to be significantly decreased in infertile groups compared the controls (p=0.0279). The GG genotype was found in a higher percentage in controls and the AA genotype was higher in infertile group (p=0.0056). Infertile homozygote (GG) and heterozygote (GA) individuals had significantly higher vitamin D levels than AA homozygote. Methylation is higher in individuals with lower vitamin D levels and AA genotype is characterized by higher methylation values.

CONCLUSION

The results provide new insights of Cdx-2 polymorphism is involved in vitamin D deficiency, highlighting the important role of epigenetic modification of vitamin D receptor and male infertility along with the genetic context.

CORRELATIONS BETWEEN POLYMORPHISMS OF ESTROGEN 1, VITAMIN D RECEPTORS AND HORMONAL PROFILE IN INFERTILE MEN

Objective

Estrogen receptor alpha (ESR1) polymorphisms (XbaI and PvuII) and vitamin D receptor (VDR) polymorphisms (FokI, BsmI, ApaI and TaqI) are the most frequently studied regarding the correlations with the infertility in males, but the results are controversial.The purpose of this study is to evaluate possible correlations between hormonal markers, VDR and ESR1 genotypes and semen analysis, in order to bring new data for a better understanding of male infertility.

Subjects and Methods

42 infertile men and 28 controls were enrolled. The polymorphisms of VDR gene (ApaI, TaqI, BsmI and FokI) and ESR1 (XbaI and PvuII) were performed by PCR-RFLP, along with hormonal markers.

Results

An important correlation between PvuII polymorphism and infertility status was revealed. A significant difference between control and infertility group regarding the presence of BsmI (A>G) and ApaI (G>T) polymorphisms was observed in infertile group, prolactin and DHEA were found to correlate significantly statistic with BsmI GG genotype, whereas ApaI AA genotype correlates with prolactin and SHBG levels.

Conclusions

By a multivariate analysis, we demonstrated a cumulative effect of some genetic variants in the hormonal status of infertile patients. Therefore, we show that specific genetic variants of ESR1 and VDR genes may jointly influence human spermatogenesis.