Association of progesterone receptor gene polymorphism with male infertility and clinical outcome of ICSI

Mitochondrial DNA levels in trophectodermal cells show no association with blastocyst development and pregnancy outcomes

Background:

In patients undergoing assisted reproduction, levels of mitochondrial DNA (mtDNA) in the trophectodermal cells of the developing blastocyst are suggested to be associated with its ability to implant. However, discrepancies exist regarding the use of mtDNA levels as a reliable biomarker to predict outcomes of assisted reproduction.

Aims:

The aim of the study is to explore the association of trophectodermal mtDNA levels to determine blastocyst quality, implantation potential of blastocyst and clinical outcomes in couples who have undergone pre-implantation genetic testing for aneuploidy (PGT-A).

Study Setting:

Private fertility centre.

Study Design:

Retrospective analysis.

Materials and Methods:

We analysed mtDNA levels in the trophectodermal cells of 287 blastocysts from 61 couples undergoing PGT-A. The levels of mtDNA were estimated by next-generation sequencing method. mtDNA levels were correlated with maternal age, blastocyst morphology, ploidy status, implantation rates, miscarriage rate and live birth rate.

Statistical Analysis Used:

Linear regression and one-way ANOVA with Tukey's all column comparison test.

Results:

The trophectodermal mtDNA levels did not correlate with maternal age. There were no significant differences in their levels in grade 1 and grade 2 blastocysts. No significant differences were seen between mtDNA levels of implanted and non-implanted blastocysts or those blastocysts that resulted in miscarriage or live birth. However, significantly lower amounts of mtDNA were seen in euploid blastocysts as compared to that in aneuploid blastocysts.

Conclusion:

mtDNA levels in the trophectodermal cells of the blastocyst do not associate with blastocyst quality (grade 1 and grade 2), implantation potential and clinical outcomes but can differentiate between aneuploid and euploid blastocysts. Our study does not support the use of trophectodermal mtDNA levels as a biomarker for blastocyst quality and predictor of clinical outcomes.

The correlation of estrogen receptor 1 and progesterone receptor genes polymorphisms with recurrent pregnancy loss in a cohort of Egyptian women

Recurrent pregnancy loss (RPL) represents one of the pregnancy complications affecting 1-3% of women. Sex hormones, progesterone and estrogen play a critical role in the maintenance of pregnancy; they are mediated by estrogen receptor 1 (ESR1) and progesterone receptor (PR) genes respectively. Polymorphisms of (ESR1) and (PR) genes are linked to RPL. We aimed to explore the association of single nucleotide polymorphisms (SNPs) of (ESR1) gene and (PR) gene with RPL in a cohort of Egyptian population (50 infertile Egyptian women who experienced RPL and 50 healthy women), using polymerase chain reaction-restriction fragment length polymorphism analysis (PCR-RFLP) of (ESR1) gene and DNA sequencing of exons 1 and 5 of (PR) gene. Genotyping of ESR1 gene SNP's: (rs2234693) and (rs9340799) revealed higher significance in cases compared to controls of p value (p = 0.006 and p = 0.001) respectively. However, the frequencies of the two variants in (PG) gene; S344T (rs3740753) (p = 0.0001) and H770H (rs1042839) (p = 0.001) were significantly higher in women compared to the healthy control women. New polymorphism P352Q was observed in 2% of cases (p = 0.0001). There was a significant association of SNP's of ESR1 and PR genes with recurrent pregnancy loss RPL. Further demographics studies should be carried on a larger number of women at risk of recurrent implantation to elucidate this SNP's association and its role in RPL women.

Genome-wide association study identifies candidate markers related to lincRNAs associated with male infertility in the Greek population

BACKGROUND

Male infertility is currently one of the most common problems faced by couples worldwide. We performed a GWAS on Greek population and gathered statistically significant SNPs in order to investigate whether they lie within or near lncRNA regions.

OBJECTIVES

The aim of this study was to investigate whether polymorphisms on or near lncRNAs affect interactions with miRNAs and can cause male infertility.

MATERIALS AND METHODS

In the present study, a GWAS was conducted, using samples from 159 individuals (83 normozoospermic individuals and 76 patients of known fertility issues). Standard procedures for quality controls and association testing were followed, based on case-control testing.

RESULTS

We detected six lncRNAs (LINC02231, LINC00347, LINC02134, NCRNA00157, LINC02493, Lnc-CASK-1) that are associated with male infertility through their interaction with miRNAs. Furthermore, we identified the genes targeted by those miRNAs and highlighted their functions in spermatogenesis and the fertilization process.

DISCUSSION AND CONCLUSION

lncRNAs are involved in spermatogenesis through their interaction with miRNAs. Thus, their study is very important, and it may contribute to the understanding of the molecular mechanisms underlying male infertility.

Paternal Age Does Not Influence the Outcomes of Assisted Reproduction in Donor Oocyte Cycles

Purpose: To study effect of paternal age on pregnancy outcomes of intracytoplasmic sperm injections (ICSI).

Methods: The present study is a retrospective analysis of 153 ICSI cycles on donor oocytes. The effect of paternal age on fertilization rates, implantation rates, total pregnancy rates, number of miscarriages and live births were analyzed.

Results: 1422 donor oocytes were injected with sperm from 153 men. Linear regression analysis revealed no association between paternal age (28-54 years) and fertilization rate. No association was found between the embryo quality and paternal age. Of the 359 embryos transferred, linear regression analysis revealed no association between paternal age and implantation rate. After correcting for maternal age, binary logistic regression analysis revealed no association between total pregnancy rates (B = 0.943, CI 0.861-1.033, P = 0.205), live birth rates (B = 1.018, CI 0.896-1.158, P = 0.562) and miscarriage rates (B = 0.944, CI 0.866-1.029, P = 0.193) and paternal age.

Conclusion: Paternal age does not seem to influence outcomes in assisted reproduction.

Deletion of GOLGA2P3Y but not GOLGA2P2Y is a risk factor for oligozoospermia

The AZFc locus on the human Y chromosome harbours several multicopy genes, some of which are required for spermatogenesis. It is believed that deletion of one or more copies of these genes is a cause of infertility in some men. GOLGA2LY is one of the genes in the AZFc locus and it exists in two copies, GOLGA2P2Y and GOLGA2P3Y. The involvement of GOLGA2LY gene copy deletions in male infertility, however, is unknown. This study aimed to investigate the association of deletions of GOLGA2P2Y and GOLGA2P3Y gene copies with male infertility and with sperm concentration and motility. The frequency of GOLGA2P3Y deletion was significantly higher in oligozoospermic men compared with normozoospermic men (7.7% versus 1.2%; P = 0.0001), whereas the frequency of GOLGA2P2Y deletion was comparable between oligozoospermic and normozoospermic men (10.3% versus 11.3%). The deletion of GOLGA2P3Y but not GOLGA2P2Y was significantly higher (P = 0.03) in men with gr/gr rearrangements, indicating that GOLGA2P3Y deletions increase the susceptibility of men with gr/gr rearrangements to oligozoospermia. Furthermore, men with GOLGA2P3Y deletion had reduced sperm concentration and motility compared with men without deletion or with deletion of GOLGA2P2Y. These findings indicate GOLGA2P3Y gene copy may be candidate AZFc gene for male infertility.

Susceptibility of gr/gr rearrangements to azoospermia or oligozoospermia is dependent on DAZ and CDY1 gene copy deletions

PURPOSE

The purpose of this study was to determine the association of AZFc subdeletions (gr/gr, b1/b3 and b2/b3) and deletion of DAZ and CDY1 gene copies with male infertility

METHODS

Three hundred twelve controls, 172 azoospermic and 343 oligozoospermic subjects were subjected to AZFc subdeletion typing by STS PCR. Deletion of DAZ and CDY1 gene copies was done using sequence family variant analysis. Sperm concentration and motility were compared between men with and without AZFc subdeletions. Effect of the AZFc subdeletions on ICSI outcome was evaluated.

RESULTS

Amongst the three AZFc subdeletions, the frequency of gr/gr was higher in oligozoospermic (10.5 %) and azoospermic (11.6 %) men as compared to controls (5.1 %). In men with AZFc subdeltions, loss of two DAZ and one CDY1 gene copy made them highly susceptible to azoospermia and severe oligozoospermia with OR of 29.7 and 26, respectively. These subdeletions had no effect on ICSI outcome, albeit there were an increased number of poor quality embryos in AZFc subdeleted group.

CONCLUSION

AZFc subdeletions are a major risk factor for male infertility in the Indian population. In the subjects with AZFc subdeletions, the deletion of DAZ and CDY1 gene copies increases its susceptibility to azoospermia or severe oligozoospermia. Since these deletions can be vertically transmitted to the future male offspring by ICSI, it will be essential to counsel the couples for the transmission of the genetic defect in the male offspring born after assisted reproduction and the risk of perpetuating infertility in future generation.