Characterization of Seminal Microbiome of Infertile Idiopathic Patients Using Third-Generation Sequencing Platform.

Since the first description of a commensal seminal microbiome using sequencing, less than a decade ago, interest in the composition of this microbiome and its relationship with fertility has been growing. Articles using next-generation sequencing techniques agree on the identification of the most abundant bacterial phyla. However, at the genus level, there is still no consensus on which bacteria are most abundant in human seminal plasma.

TMT-Based Proteomic Analysis of Human Spermatozoa from Unexplained Recurrent Miscarriage Patients before and after Oral Antioxidant Treatment.

Recently, sperm quality and the presence of double-stranded breaks (DSB) has been pointed out as a possible cause of recurrent miscarriage, and the use of antioxidants has expanded as a treatment for male infertility. The aim of the present study was to analyze the proteomic effects of antioxidants on sperm from RM patients with high incidence of DSB. Proteomic analysis was performed using a tandem mass tag labeling technique, and subsequently compared with the PANTHER database for DEPs, and the STRING database for protein-protein interactions (PPI).

Seminal Microbiota of Idiopathic Infertile Patients and Its Relationship With Sperm DNA Integrity.

The development of new biomarkers for human male infertility is crucial to improve the diagnosis and the prognosis of this disease. Recently, seminal microbiota was shown to be related to sperm quality parameters, suggesting an effect in human fertility and postulating it as a biomarker candidate. However, its relationship to sperm DNA integrity has not been studied yet.

Sperm chromatin condensation and single- and double-stranded DNA damage as important parameters to define male factor related recurrent miscarriage.

The aim of the present work is to characterize the relationship between sperm protamine deficiency and single- and double-stranded DNA damage and to assess the diagnostic potential of chromomycin A3 (CMA3). For that purpose, semen samples from 90 human males with different clinical features were included (fertile donors, patients with recurrent pregnancy loss [RPL], and infertile patients). DNA condensation was analyzed by CMA3 and different types of DNA fragmentation were analyzed through the comet assay.

Relationship of Seminal Oxidation-Reduction Potential with Sperm DNA Integrity and pH in Idiopathic Infertile Patients.

Seminal oxidative stress (OS) is one of the most promising factors to describe the causes of idiopathic male infertility. Redox balance is essential in several biological processes related to fertility, so alterations such as high reactive oxygen species (ROS) levels or low antioxidant agent levels can compromise it. MiOXSYS has been developed to evaluate the seminal static oxidation-reduction potential (sORP) and it has been proposed as an effective diagnostic biomarker.

Novel Double Factor PGT strategy analyzing blastocyst stage embryos in a single NGS procedure.

In families at risk from monogenic diseases affected offspring, it is fundamental the development of a suitable Double Factor Preimplantation Genetic Testing (DF-PGT) method for both single-gene analysis and chromosome complement screening. Aneuploidy is not only a major issue in advanced-maternal-age patients and balanced translocation carriers, but also the aneuploidy rate is extremely high in patients undergoing in vitro fertilization (IVF), even in young donors. To adequate NGS technology to the DF-PGT strategy four different whole genome amplification systems (Sureplex, MALBAC, and two multiple displacement amplification systems-MDA) were tested using TruSight One panel on cell lines and blastocyst trophectoderm biopsies-TE.

An exploratory study of predisposing genetic factors for DiGeorge/velocardiofacial syndrome.

DiGeorge/velocardiofacial syndrome (DGS/VCFS) is a disorder caused by a 22q11.2 deletion mediated by non-allelic homologous recombination (NAHR) between low-copy repeats (LCRs). We have evaluated the role of LCR22 genomic architecture and PRDM9 variants as DGS/VCFS predisposing factors.

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Introducción: la infertilidad es un problema global en aumento. Se estima que aproximadamente un 15% de las parejas en edad reproductiva tiene dificultades a la hora de concebir. De estas, alrededor de la mitad presentan uno o varios factores masculinos asociados a infertilidad o subfertilidad, aislados o en combinación con problemas de origen femenino.

Analysis of invdupdel(8p) rearrangement: Clinical, cytogenetic and molecular characterization.

Inverted duplication 8p associated with deletion of the short arms of chromosome 8 (invdupdel[8p]) is a relatively uncommon complex chromosomal rearrangement, with an estimated incidence of 1 in 10,000-30,000 live borns. The chromosomal rearrangement consists of a deletion of the telomeric region (8p23-pter) and an inverted duplication of the 8p11.2-p22 region.

Multiple determinations of sperm DNA fragmentation show that varicocelectomy is not indicated for infertile patients with subclinical varicocele.

Varicocele is one of the most common causes of low semen quality, which is reflected in high percentages of sperm cells with fragmented DNA. While varicocelectomy is usually performed to ameliorate a patient's fertility, its impact on sperm DNA integrity in the case of subclinical varicocele is poorly documented. In this study, multiple DNA fragmentation analyses (TUNEL, SCD, and SCSA) were performed on semen samples from sixty infertile patients with varicocele (15 clinical varicoceles, 19 clinical varicoceles after surgical treatment, 16 subclinical varicoceles, and 10 subclinical varicoceles after surgical treatment).

Genetic recombination variation in wild Robertsonian mice: on the role of chromosomal fusions and Prdm9 allelic background.

Despite the existence of formal models to explain how chromosomal rearrangements can be fixed in a population in the presence of gene flow, few empirical data are available regarding the mechanisms by which genome shuffling contributes to speciation, especially in mammals. In order to shed light on this intriguing evolutionary process, here we present a detailed empirical study that shows how Robertsonian (Rb) fusions alter the chromosomal distribution of recombination events during the formation of the germline in a Rb system of the western house mouse (Mus musculus domesticus). Our results indicate that both the total number of meiotic crossovers and the chromosomal distribution of recombination events are reduced in mice with Rb fusions and that this can be related to alterations in epigenetic signatures for heterochromatinization.

Evolution of recombination in eutherian mammals: insights into mechanisms that affect recombination rates and crossover interference.

Recombination allows faithful chromosomal segregation during meiosis and contributes to the production of new heritable allelic variants that are essential for the maintenance of genetic diversity. Therefore, an appreciation of how this variation is created and maintained is of critical importance to our understanding of biodiversity and evolutionary change. Here, we analysed the recombination features from species representing the major eutherian taxonomic groups Afrotheria, Rodentia, Primates and Carnivora to better understand the dynamics of mammalian recombination.

Differential clustering of sperm subpopulations in infertile males with clinical varicocele and carriers of rearranged genomes.

Some methods for determining sperm DNA fragmentation, such as the sperm chromatin structure assay (SCSA) and the sperm chromatin dispersion test (SCD), provide additional information about particular subgroups of spermatozoa with specific irregularities. Thus, SCSA recognizes a specific sperm subpopulation, the high-DNA stainability sperm subpopulation (HDS), and SCD recognizes the so-called DNA-degraded sperm (DDS) subpopulation. Although some studies associate the presence of these subpopulations with specific aspects related to infertility, the relationship between both sperm subpopulations and their preponderance in specific clinical groups of infertile males has not been extensively investigated.

Detection of unbalanced chromosome segregations in preimplantation genetic diagnosis of translocations by short comparative genomic hibridization.

Objective: To apply a comprehensive chromosomal screening through short comparative genomic hybridization (CGH) in the preimplantation genetic diagnosis (PGD) of translocations.

Design: Clinical research study.

Setting: A PGD laboratory and two IVF clinics.

Dynamics of sperm DNA fragmentation in patients carrying structurally rearranged chromosomes.

This investigation was conducted to assess the baseline level of sperm DNA fragmentation (SDF) in a cohort of patients presenting chromosomal rearrangements (nine reciprocal translocations and two inversions). In a separate experiment, a dynamic analysis to calculate the rate of SDF (rSDF), after a varying period of sperm storage (0 h, 1 h, 4 h, 8 h and 24 h) at 37 °C, was performed. Results were compared with eight fertile donors.

Sperm DNA integrity and meiotic behavior assessment in an infertile male carrier of a 9qh+++ polymorphism.

Although several reports on male infertility suggest a relationship between chromosome 9 polymorphisms and infertility, the effects on the phenotype have not been extensively reported. In this study, an infertile patient was found to carry a 9qh+++ chromosome. The flow cytometric TUNEL assay and SCD test have been applied to characterize sperm DNA integrity.

Protamine 1 to protamine 2 ratio correlates with dynamic aspects of DNA fragmentation in human sperm.

Objective: To investigate the relationship between the protamine 1 to protamine 2 (P1/P2) ratio and the rate of sperm DNA fragmentation in sperm samples from human males with proven fertility and three different cohorts of male patients.

Design: P1/P2 ratio was analyzed using acid-urea polyacrylamide acid-urea gels electrophoresis (PAGE). Sperm DNA fragmentation using sperm chromatin dispersion methodology was analyzed after 0, 4, 8, and 24 hours of incubation at 37°C.

Reliability of short comparative genomic hybridization in fibroblasts and blastomeres for a comprehensive aneuploidy screening: first clinical application.

Background: Comparative genomic hybridization (CGH) is a valuable alternative to fluorescence in situ hybridization (FISH) for preimplantation genetic screening (PGS) because it allows full karyotype analysis. However, this approach requires the cryopreservation of biopsied embryos until results are available. The aim of this study is to reduce the hybridization period of CGH, in order to make this short-CGH technique suitable for PGS of Day-3 embryos, avoiding the cryopreservation step.

Outcome of twin babies free of Von Hippel-Lindau disease after a double-factor preimplantation genetic diagnosis: monogenetic mutation analysis and comprehensive aneuploidy screening.

Objective: To increase the embryo implantation rate, a double-factor preimplantation genetic diagnosis (DF-PGD) was performed, selecting for transfer potentially euploid evolved embryos free of the mutation responsible for Von Hippel-Lindau syndrome (VHL).

Design: Case report.

Settings: Medical university center and a private IVF center.

DNA fragmentation and meiotic segregation in sperm of carriers of a chromosomal structural abnormality.

Objective: To determine the meiotic segregation and DNA fragmentation in spermatozoa of carriers of a chromosomal structural abnormality.

Design: Case series.

Setting: University hospital.

Reduced meiotic recombination on the XY bivalent is correlated with an increased incidence of sex chromosome aneuploidy in men with non-obstructive azoospermia.

Both aberrant meiotic recombination and an increased frequency of sperm aneuploidy have been observed in infertile men. However, this association has not been demonstrated within individual men. The purpose of this study was to determine the association between the frequency of recombination observed in pachytene spermatocytes and the frequency of aneuploidy in sperm from the same infertile men.

Birth of a healthy boy after a double factor PGD in a couple carrying a genetic disease and at risk for aneuploidy: case report.

Preimplantation genetic diagnosis (PGD) for monogenic diseases is widely applied, allowing the transfer to the uterus of healthy embryos. PGD is also employed for the detection of chromosome abnormalities for couples at high risk of producing aneuploid embryos, such as advanced maternal (>35 years). A significant number of patients requesting PGD for monogenic diseases are also indicated for chromosome testing.

Variation in crossover interference levels on individual chromosomes from human males.

Crossovers (COs) generated by homologous recombination ensure the proper segregation of chromosomes during meiosis. COs exhibit interference, which leads to widely spaced COs along chromosomes. Strong positive CO interference has been found in humans.

The relationship between meiotic recombination in human spermatocytes and aneuploidy in sperm.

Background: We have previously demonstrated that a decreased recombination frequency between human X and Y chromosomes is associated with the production of aneuploid 24,XY sperm. This study's aim was to determine the relationship between recombination frequency in human pachytene spermatocytes and aneuploidy frequencies in individual chromosomes in sperm from the same men.

Methods: Six previously fertile vasectomy reversal patients donated testicular tissue for meiotic analysis of pachytene spermatocytes using immunocytogenetic techniques for visualization of the synaptonemal complex and recombination sites (MLH1).