Personalized prediction of the secondary oocytes number after ovarian stimulation: A machine learning model based on clinical and genetic data.

Controlled ovarian stimulation is tailored to the patient based on clinical parameters but estimating the number of retrieved metaphase II (MII) oocytes is a challenge. Here, we have developed a model that takes advantage of the patient's genetic and clinical characteristics simultaneously for predicting the stimulation outcome. Sequence variants in reproduction-related genes identified by next-generation sequencing were matched to groups of various MII oocyte counts using ranking, correspondence analysis, and self-organizing map methods. The gradient boosting machine technique was used to train models on a clinical dataset of 8,574 or a clinical-genetic dataset of 516 ovarian stimulations. The clinical-genetic model predicted the number of MII oocytes better than that based on clinical data. Anti-Müllerian hormone level and antral follicle count were the two most important predictors while a genetic feature consisting of sequence variants in the GDF9, LHCGR, FSHB, ESR1, and ESR2 genes was the third. The combined contribution of genetic features important for the prediction was over one-third of that revealed for anti-Müllerian hormone. Predictions of our clinical-genetic model accurately matched individuals' actual outcomes preventing over- or underestimation. The genetic data upgrades the personalized prediction of ovarian stimulation outcomes, thus improving the in vitro fertilization procedure.

Mitochondrial DNA Copy Number in Cleavage Stage Human Embryos-Impact on Infertility Outcome.

A retrospective case control study was undertaken at the molecular biology department of a private center for reproductive medicine in order to determine whether any correlation exists between mitochondrial DNA (mtDNA) content of cleavage-stage preimplantation embryos and their developmental potential. A total of 69 couples underwent IVF treatment (averaged women age: 36.5, SD 4.9) and produced a total of 314 embryos. A single blastomere was biopsied from each embryo at the cleavage stage (day-3 post-fertilization) subjected to low-pass next generation sequencing (NGS), for the purpose of detecting aneuploidy. For each sample, the number of mtDNA reads obtained after analysis using NGS was divided by the number of reads attributable to the nuclear genome. The mtDNA copy number amount was found to be higher in aneuploid embryos than in those that were euploid (mean mtDNA ratio ± SD: 6.3 ± 7.5 versus 7.1 ± 5.8, p < 0.004; U Mann−Whitney test), whereas no statistically significant differences in mtDNA content were seen in relation to embryo morphology (6.6 ± 4.8 vs. 8.5 ± 13.6, p 0.09), sex (6.6 ± 4.1 vs. 6.2 ± 6.8, p 0.16), maternal age (6.9 ± 7.8 vs. 6.7 ± 4.5, p 0.14) or its ability to implant (7.4 ± 6.6 vs. 5.1 ± 4.6, p 0.18). The mtDNA content cannot serve as a useful biomarker at this point in development. However, further studies investigating both quantitative and qualitative aspects of mtDNA are still required to fully evaluate the relationship between mitochondrial DNA and human reproduction.

Effect of next-generation sequencing in preimplantation genetic testing on live birth ratio.

The present study analysed live birth ratios in frozen embryo transfer (FET) cycles where embryo ploidy status was determined with preimplantation genetic testing (PGT) using next-generation sequencing (NGS). PGT was performed on trophectoderm cells biopsied at the blastocyst stage. The present prospective cohort study included 112 women undergoing frozen embryo transfer, with NGS PGT. The control group consisted of 85 patients who underwent the IVF procedure with FET planned for a subsequent cycle. The live birth rate per cycle was higher by ~18.5 percentage points in the investigated compared with control group (42.0% vs 23.5% respectively; P=0.012). The differences between the study and control groups were also significant for clinical pregnancy (42.0% vs 23.5% respectively; P=0.012), implantation (41.2% vs 22.2% respectively; P=0.001) and pregnancy loss rates (9.6% vs 28.6% respectively; P=0.027). The results show that PGT NGS is a useful method for embryo selection and it may be implemented in routine clinical practice with propitious results.

[First in the world application of next generation sequencing in preimplantation genetic diagnostics in clinical practice - a case report]. / Pierwsze w swiecie zastosowanie sekwencjonowania nastepnej generacji w diagnostyce przedimplantacyjnej w praktyce klinicznej - opis przypadku.

Preimplantation genetic diagnosis (PGD) is a well established method for detecting genetic abnormalities during the course of infertility treatment, resulting in thousands of healthy newborns delivered worldwide. PGD with next generation sequencing (NGS) provides new possibilities for diagnosis and new parameters for evaluation. The use of next-generation DNA sequencing technique has lead to great progress in the human genome analysis. The aim of this study was molecular analysis using next generation sequencing technique of embryos from a couple suffering from recurrent pregnancy losses. As a result of in vitro fertilization procedure, seven embryos were created. Seven blastomeres, one from each embryo, were analyzed. Transfer of two blastocysts in a fresh cycle resulted in the singleton pregnancy. Healthy baby girl was delivered via caesarean section after 28 weeks of gestation (weight: 1250g, Apgar score: 8/9). The reason for the premature labor was likely caused by mother's pneumonia. This is the first case of clinical use of the NGS in PGD in fresh cycle after blastomere biopsy.

Next generation sequencing for preimplantation genetic testing of blastocysts aneuploidies in women of different ages.

Most of the current preimplantation genetic screening of aneuploidies tests are based on the low quality and low density comparative genomic hybridization arrays. The results are based on fewer than 2,700 probes. Our main outcome was the association of aneuploidy rates and the women's age. Between August-December 2013, 198 blastocysts from women (mean age 36.3+-4.6) undergoing in vitro fertilization underwent routine trophectoderm biopsy. NGS was performed on Ion Torrent PGM (Life Technologies). The results were analyzed in five age groups (<31, 31-35, 36-38, 39-40 and >40). 85 blastocysts were normal according to NGS results. The results in the investigated groups were (% of normal blastocyst in each group): <31 (41.9%), 31-35 (47.6%), 36-38 (47.8%), 39-40 (37.7%) and >40 (38.5%). Our study suggests that NGS PGD is applicable for routine preimplantation genetic testing. It allows also for easy customization of the procedure for each individual patient making personalized diagnostics a reality.

Healthy Baby Born to a Robertsonian Translocation Carrier following Next-Generation Sequencing-Based Preimplantation Genetic Diagnosis: A Case Report.

Preimplantation genetic diagnosis (PGD) is well established method for treatment of genetic problems associated with infertility. Moreover, PGD with next-generation sequencing (NGS) provide new possibilities for diagnosis and new parameters for evaluation in, for example, aneuploidy screening. The aim of the study was to report the successful pregnancy outcome following PGD with NGS as the method for 24 chromosome aneuploidy screening in the case of Robertsonian translocation. Day 3 embryos screening for chromosomal aneuploidy was performed in two consecutive in vitro fertilization (IVF) cycles, first with fluorescent in situ hybridization (FISH), and then with NGS-based protocol. In each IVF attempt, three embryos were biopsied. Short duration of procedures enabled fresh embryo transfer without the need for vitrification. First IVF cycle with the embryo selected using PGD analysis with the FISH method ended with pregnancy loss in week 8. The second attempt with NGS-based aneuploidy screening led to exclusion of the following two embryos: one embryo with 22 monosomy and one with multiple aneuploidies. The transfer of the only euploid blastocyst resulted in the successful pregnancy outcome. The identification of the euploid embryo based on the NGS application was the first successful clinical application of NGS-based PGD in the case of the Robertsonian translocation carrier couple.

Routine use of next-generation sequencing for preimplantation genetic diagnosis of blastomeres obtained from embryos on day 3 in fresh in vitro fertilization cycles.

OBJECTIVE: To determine the usefulness of semiconductor-based next-generation sequencing (NGS) for cleavage-stage preimplantation genetic diagnosis (PGD) of aneuploidy. DESIGN: Prospective case-control study. SETTING: A private center for reproductive medicine. PATIENT(S): A total of 45 patients underwent day-3 embryo biopsy with PGD and fresh cycle transfer. Additionally, 53 patients, matched according to age, anti-Müllerian hormone levels, antral follicles count, and infertility duration were selected as controls. INTERVENTION(S): Choice of embryos for transfer was based on the PGD NGS results. MAIN OUTCOME MEASURE(S): Clinical pregnancy rate (PR) per embryo transfer (ET) was the primary outcome. Secondary outcomes were implantation and miscarriage rates. RESULT(S): The PR per transfer was higher in the NGS group (84.4% vs. 41.5%). The implantation rate (61.5% vs. 34.8%) was higher in the NGS group. The miscarriage rate was similar in the 2 groups (2.8% vs. 4.6%). CONCLUSION(S): We demonstrate the technical feasibility of NGS-based PGD involving cleavage-stage biopsy and fresh ETs. Encouraging data were obtained from a prospective trial using this approach, arguing that cleavage-stage NGS may represent a valuable addition to current aneuploidy screening methods. These findings require further validation in a well-designed randomized controlled trial. CLINICAL TRIAL REGISTRATION NUMBER: ACTRN12614001035617.

Co-evolution-driven switch of J-protein specificity towards an Hsp70 partner.

Molecular mechanisms by which protein-protein interactions are preserved or lost after gene duplication are not understood. Taking advantage of the well-studied yeast mtHsp70:J-protein molecular chaperone system, we considered whether changes in partner proteins accompanied specialization of gene duplicates. Here, we report that existence of the Hsp70 Ssq1, which arose by duplication of the gene encoding multifunction mtHsp70 and specializes in iron-sulphur cluster biogenesis, correlates with functional and structural changes in the J domain of its J-protein partner Jac1. All species encoding this shorter alternative version of the J domain share a common ancestry, suggesting that all short JAC1 proteins arose from a single deletion event. Construction of a variant that extended the length of the J domain of a 'short' Jac1 enhanced its ability to partner with multifunctional Hsp70. Our data provide a causal link between changes in the J protein partner and specialization of duplicate Hsp70.

Roles for the human ATP-dependent Lon protease in mitochondrial DNA maintenance.

Human mitochondrial Lon is an ATP-powered proteolytic machine that specifically binds to single-stranded G-rich DNA and RNA in vitro. However, it is unknown whether Lon binds mitochondrial DNA (mtDNA) in living cells or functions in mtDNA integrity. Here, we demonstrate that Lon interacts with the mitochondrial genome in cultured cells using mtDNA immunoprecipitation (mIP). Lon associates with sites distributed primarily within one-half of the genome and preferentially with the control region for mtDNA replication and transcription. Bioinformatic analysis of mIP data revealed a G-rich consensus sequence. Consistent with these findings, in vitro experiments showed that the affinity of Lon for single-stranded DNA oligonucleotides correlates with conformity to this consensus. To examine the role of Lon in mtDNA maintenance, cells carrying an inducible short hairpin RNA for Lon depletion were used. In control and Lon-depleted cells, mtDNA copy number was essentially the same in the presence or absence of oxidative stress. However when oxidatively stressed, control cells exhibited an increased frequency of mtDNA lesions, whereas Lon-depleted cells showed little if any mtDNA damage. This suggests that oxidative mtDNA damage is permitted when Lon is present and prevented when Lon is substantially depleted. Upon oxidative stress, mIP showed reduced Lon binding to mtDNA; however binding to the control region was unaffected. It is unlikely that oxidative modification of Lon blocks its ability to bind DNA in vivo as results show that oxidized purified Lon retains sequence-specific DNA binding. Taken together, these results demonstrate that mtDNA binding is a physiological function of Lon and that cellular levels of Lon influence sensitivity to mtDNA damage. These findings suggest roles for Lon in linking protein and mtDNA quality control.

Evolution of mitochondrial chaperones utilized in Fe-S cluster biogenesis.

Biogenesis of Fe-S clusters is an essential process [1]. In both Escherichia coli and Saccharomyces cerevisiae, insertion of clusters into an apoprotein requires interaction between a scaffold protein on which clusters are assembled and a molecular chaperone system--an unusually specialized mitochondrial Hsp70 (mtHsp70) and its J protein cochaperone [2]. It is generally assumed that mitochondria inherited their Fe-S cluster assembly machinery from prokaryotes via the endosymbiosis of a bacterium that led to formation of mitochondria. Indeed, phylogenetic analyses demonstrated that the S. cerevisiae J protein, Jac1, and the scaffold, Isu, are orthologous to their bacterial counterparts [3, 4]. However, our analyses indicate that the specialized mtHsp70, Ssq1, is only present in a subset of fungi; most eukaryotes have a single mtHsp70, Ssc1. We propose that an Hsp70 having a role limited to Fe-S cluster biogenesis arose twice during evolution. In the fungal lineage, the gene encoding multifunctional mtHsp70, Ssc1, was duplicated, giving rise to specialized Ssq1. Therefore, Ssq1 is not orthologous to the specialized Hsp70 from E. coli (HscA), but shares a striking level of convergence at the biochemical level. Thus, in the vast majority of eukaryotes, Jac1 and Isu function with the single, multifunctional mtHsp70 in Fe-S cluster biogenesis.