Preimplantation development of embryos in women of advanced maternal age

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O. V. Chaplia

2014-04-01

Full Text Available In order to reveal the influence of genetic component on the early embryo development, the retrospective study of morphokinetic characteristics of 717 embryos subjected to preimplantation genetic testing was conducted. Blastomere biopsy for FISH-based preimplantation genetic screening of 7 chromosomes was performed on the third day of culture, while embryo developmental potential and morphological features at the cleavage and blastulation stage were studied regarding maternal age particularly in the group of younger women and patients older than 36. Results of genetic testing revealed that euploid embryos rate gradually decreased with maternal age comprising 39.9% in young women group and 25.3% of specimen belonging to elder patients. At the cleavage stage, morphological characteristics of aneuploid and euploid embryos didn’t differ significantly regardless of the age of patients that could be accounted for the transcriptional silence of embryo genome till the third day of its development. However, in case of prolonged culture chromosomally balanced embryos rarely faced developmental arrest (in 7.9% and formed blastocysts half more frequently compared to aberrant embryos (respectively 75.6 versus 49.8%. Nevertheless, no substantial difference was found between blastocyst formation rate among embryos with similar genetic component regardless of the maternal age. Taking into consideration high rate of chromosomally unbalanced embryos specific to patients of advanced maternal age, the relative proportion of aneuplouid blastocysts was significantly higher in this group of embryos. Thus, without genetic screening there is a possibility of inaccurate selection of embryos for women of advanced reproductive age for transfer procedure even in case of prolonged culture. Consequently, increase of aneuploid embryos frequency associated with permanent preimplantation natural selection effectiveness along with the postimplantation natural selection failure

Expression of the CTCF gene in bovine oocytes and preimplantation embryos

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Álvaro F.L. Rios

2007-01-01

Full Text Available The CCCTC - binding factor (CTCF is a protein involved in repression, activation, hormone-inducible gene silencing, functional reading of imprinted genes and X-chromosome inactivation. We analyzed CTCF gene expression in bovine peripheral blood, oocytes and in different cellular stages (2-4 cells, 8-16 cells, 16-32 cells, morulae, and blastocysts of in vitro fertilized embryos. This is the first report of CTCF expression in oocytes and preimplantation bovine embryos and has implications for the production of embryonic stem cells and the development of novel medical technologies for humans.

Protein Expression Landscape of Mouse Embryos during Pre-implantation Development

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Yawei Gao

2017-12-01

Full Text Available Pre-implantation embryo development is an intricate and precisely regulated process orchestrated by maternally inherited proteins and newly synthesized proteins following zygotic genome activation. Although genomic and transcriptomic studies have enriched our understanding of the genetic programs underlying this process, the protein expression landscape remains unexplored. Using quantitative mass spectrometry, we identified nearly 5,000 proteins from 8,000 mouse embryos of each stage (zygote, 2-cell, 4-cell, 8-cell, morula, and blastocyst. We found that protein expression in zygotes, morulas, and blastocysts is distinct from 2- to 8-cell embryos. Analysis of protein phosphorylation identified critical kinases and signal transduction pathways. We highlight key factors and their important roles in embryo development. Combined analysis of transcriptomic and proteomic data reveals coordinated control of RNA degradation, transcription, and translation and identifies previously undefined exon-junction-derived peptides. Our study provides an invaluable resource for further mechanistic studies and suggests core factors regulating pre-implantation embryo development.

Factors affecting the gene expression of in vitro cultured human preimplantation embryos

NARCIS (Netherlands)

Mantikou, E.; Jonker, M.J.; Wong, K.M.; van Montfoort, A.P.A.; de Jong, M.; Breit, T.M.; Repping, S.; Mastenbroek, S.

2016-01-01

STUDY QUESTION: What is the relative effect of common environmental and biological factors on transcriptome changes during human preimplantation development? SUMMARY ANSWER: Developmental stage and maternal age had a larger effect on the global gene expression profile of human preimplantation

Saviour embryos? Preimplantation genetic diagnosis as a therapeutic technology.

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Sparrow, Robert; Cram, David

2010-05-01

The creation of 'saviour siblings' is one of the most controversial uses of preimplantation genetic diagnosis (PGD). This paper outlines and invites ethical discussion of an extension of this technology, namely, the creation of 'saviour embryos' to serve as a source of stem cells to be used in potentially life-saving therapy for an existing child. A number of analogies between this hypothetical use of PGD and existing uses of IVF are offered and, in addition, between saviour embryos and proposed therapeutic applications of stem cell technology. The ethical significance of a number of disanalogies between these cases are explored and investigated. While the creation of saviour embryos would involve a significant shift in the rationale for IVF and PGD, it is suggested here that the urgent need of an existing individual should be prioritised over any obligations that might exist in relation to the creation or destruction of human embryos. Copyright (c) 2009 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Mouse preimplantation embryo responses to culture medium osmolarity include increased expression of CCM2 and p38 MAPK activation

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Watson Andrew J

2007-01-01

Full Text Available Abstract Background Mechanisms that confer an ability to respond positively to environmental osmolarity are fundamental to ensuring embryo survival during the preimplantation period. Activation of p38 mitogen-activated protein kinase (MAPK occurs following exposure to hyperosmotic treatment. Recently, a novel scaffolding protein called Osmosensing Scaffold for MEKK3 (OSM was linked to p38 MAPK activation in response to sorbitol-induced hypertonicity. The human ortholog of OSM is cerebral cavernous malformation 2 (CCM2. The present study was conducted to investigate whether CCM2 is expressed during mouse preimplantation development and to determine whether this scaffolding protein is associated with p38 MAPK activation following exposure of preimplantation embryos to hyperosmotic environments. Results Our results indicate that Ccm2 along with upstream p38 MAPK pathway constituents (Map3k3, Map2k3, Map2k6, and Map2k4 are expressed throughout mouse preimplantation development. CCM2, MAP3K3 and the phosphorylated forms of MAP2K3/MAP2K6 and MAP2K4 were also detected throughout preimplantation development. Embryo culture in hyperosmotic media increased p38 MAPK activity in conjunction with elevated CCM2 levels. Conclusion These results define the expression of upstream activators of p38 MAPK during preimplantation development and indicate that embryo responses to hyperosmotic environments include elevation of CCM2 and activation of p38 MAPK.

Cryopreservation of preimplantation embryos of cattle, sheep, and goats.

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Youngs, Curtis R

2011-08-05

Preimplantation embryos from cattle, sheep, and goats may be cryopreserved for short- or long-term storage. Preimplantation embryos consist predominantly of water, and the avoidance of intracellular ice crystal formation during the cryopreservation process is of paramount importance to maintain embryo viability. Embryos are placed into a hypertonic solution (1.4 - 1.5 M) of a cryoprotective agent (CPA) such as ethylene glycol (EG) or glycerol (GLYC) to create an osmotic gradient that facilitates cellular dehydration. After embryos reach osmotic equilibrium in the CPA solution, they are individually loaded in the hypertonic CPA solution into 0.25 ml plastic straws for freezing. Embryos are placed into a controlled rate freezer at a temperature of -6°C. Ice crystal formation is induced in the CPA solution surrounding the embryo, and crystallization causes an increase in the concentration of CPA outside of the embryo, causing further cellular dehydration. Embryos are cooled at a rate of 0.5°C/min, enabling further dehydration, to a temperature of -34°C before being plunged into liquid nitrogen (-196°C). Cryopreserved embryos must be thawed prior to transfer to a recipient (surrogate) female. Straws containing the embryos are removed from the liquid nitrogen dewar, held in room temperature air for 3 to 5 sec, and placed into a 37°C water bath for 25 to 30 sec. Embryos cryopreserved in GLYC are placed into a 1 M solution of sucrose for 10 min for removal of the CPA before transfer to a recipient (surrogate) female. Embryos cryopreserved in EG, however, may be directly transferred to the uterus of a recipient.

Gene Coexpression and Evolutionary Conservation Analysis of the Human Preimplantation Embryos

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Tiancheng Liu

2015-01-01

Full Text Available Evolutionary developmental biology (EVO-DEVO tries to decode evolutionary constraints on the stages of embryonic development. Two models—the “funnel-like” model and the “hourglass” model—have been proposed by investigators to illustrate the fluctuation of selective pressure on these stages. However, selective indices of stages corresponding to mammalian preimplantation embryonic development (PED were undetected in previous studies. Based on single cell RNA sequencing of stages during human PED, we used coexpression method to identify gene modules activated in each of these stages. Through measuring the evolutionary indices of gene modules belonging to each stage, we observed change pattern of selective constraints on PED for the first time. The selective pressure decreases from the zygote stage to the 4-cell stage and increases at the 8-cell stage and then decreases again from 8-cell stage to the late blastocyst stages. Previous EVO-DEVO studies concerning the whole embryo development neglected the fluctuation of selective pressure in these earlier stages, and the fluctuation was potentially correlated with events of earlier stages, such as zygote genome activation (ZGA. Such oscillation in an earlier stage would further affect models of the evolutionary constraints on whole embryo development. Therefore, these earlier stages should be measured intensively in future EVO-DEVO studies.

Toxicity of beauvericin on porcine oocyte maturation and preimplantation embryo development

NARCIS (Netherlands)

Schoevers, Eric J; Santos, Regiane R; Fink-Gremmels, Johanna; Roelen, Bernard A J

2016-01-01

Beauvericin (BEA) is one of many toxins produced by Fusarium species that contaminate feed materials. The aim of this study was to assess its effects on porcine oocyte maturation and preimplantation embryo development. Cumulus-oocyte-complexes and developing embryos were exposed to BEA and cultured

Functional analysis of lysosomes during mouse preimplantation embryo development.

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Tsukamoto, Satoshi; Hara, Taichi; Yamamoto, Atsushi; Ohta, Yuki; Wada, Ayako; Ishida, Yuka; Kito, Seiji; Nishikawa, Tetsu; Minami, Naojiro; Sato, Ken; Kokubo, Toshiaki

2013-01-01

Lysosomes are acidic and highly dynamic organelles that are essential for macromolecule degradation and many other cellular functions. However, little is known about lysosomal function during early embryogenesis. Here, we found that the number of lysosomes increased after fertilization. Lysosomes were abundant during mouse preimplantation development until the morula stage, but their numbers decreased slightly in blastocysts. Consistently, the protein expression level of mature cathepsins B and D was high from the one-cell to morula stages but low in the blastocyst stage. One-cell embryos injected with siRNAs targeted to both lysosome-associated membrane protein 1 and 2 (LAMP1 and LAMP2) were developmentally arrested at the two-cell stage. Pharmacological inhibition of lysosomes also caused developmental retardation, resulting in accumulation of lipofuscin. Our findings highlight the functional changes in lysosomes in mouse preimplantation embryos.

Sexing bovine pre-implantation embryos using the polymerase ...

African Journals Online (AJOL)

Yomi

2012-03-06

Mar 6, 2012 ... with pregnancy follow-up to October 2008. Hum. Reprod. 25(11):. 2685-2707. Harper JC, Sengupta SB (2012) Preimplantation genetic diagnosis: State of the ART 2011. Hum. Genet. 131(2): 175-186. Hasler JF (2003). The current status and future of commercial embryo transfer in cattle. Anim. Reprod. Sci.

Melatonin protect the development of preimplantation mouse embryos from sodium fluoride-induced oxidative injury.

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Zhao, Jiamin; Fu, Beibei; Peng, Wei; Mao, Tingchao; Wu, Haibo; Zhang, Yong

2017-09-01

Recently study shows that melatonin can protect embryos from the culture environment oxidative stress. However, the protective effect of melatonin on the mouse development of preimplantation embryos under sodium fluoride (NaF) induced oxidative stress is still unclear. Here, we showed that exposure to NaF significantly increased the reactive oxygen species (ROS) level, decreased the blastocyst formation rates, and increased the fragmentation, apoptosis and retardation of blastocysts in the development of mouse preimplantation embryos. However, the protective of melatonin remarkable increased the of blastocyst formation rates, maintained mitochondrial function and total antioxidant capacity by clearing ROS. Importantly the data showed that melatonin improved the activity of enzymatic antioxidants, including glutathione(GSH), superoxide dismutase(SOD), and malonaldehyde (MDA), and increased the expression levels of antioxidative genes. Taken together, our results indicate that melatonin prevent NaF-induced oxidative damage to mouse preimplantation embryo through down regulation of ROS level, stabilization of mitochondrial function and modulation of the activity of antioxidases and antioxidant genes. Copyright © 2017 Elsevier B.V. All rights reserved.

Transcriptome analyses of rhesus monkey preimplantation embryos reveal a reduced capacity for DNA double-strand break repair in primate oocytes and early embryos

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Wang, Xinyi; Liu, Denghui; He, Dajian; Suo, Shengbao; Xia, Xian; He, Xiechao; Han, Jing-Dong J.; Zheng, Ping

2017-01-01

Preimplantation embryogenesis encompasses several critical events including genome reprogramming, zygotic genome activation (ZGA), and cell-fate commitment. The molecular basis of these processes remains obscure in primates in which there is a high rate of embryo wastage. Thus, understanding the factors involved in genome reprogramming and ZGA might help reproductive success during this susceptible period of early development and generate induced pluripotent stem cells with greater efficiency. Moreover, explaining the molecular basis responsible for embryo wastage in primates will greatly expand our knowledge of species evolution. By using RNA-seq in single and pooled oocytes and embryos, we defined the transcriptome throughout preimplantation development in rhesus monkey. In comparison to archival human and mouse data, we found that the transcriptome dynamics of monkey oocytes and embryos were very similar to those of human but very different from those of mouse. We identified several classes of maternal and zygotic genes, whose expression peaks were highly correlated with the time frames of genome reprogramming, ZGA, and cell-fate commitment, respectively. Importantly, comparison of the ZGA-related network modules among the three species revealed less robust surveillance of genomic instability in primate oocytes and embryos than in rodents, particularly in the pathways of DNA damage signaling and homology-directed DNA double-strand break repair. This study highlights the utility of monkey models to better understand the molecular basis for genome reprogramming, ZGA, and genomic stability surveillance in human early embryogenesis and may provide insights for improved homologous recombination-mediated gene editing in monkey. PMID:28223401

Transcriptomic changes in the pre-implantation uterus highlight histotrophic nutrition of the developing marsupial embryo.

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Whittington, Camilla M; O'Meally, Denis; Laird, Melanie K; Belov, Katherine; Thompson, Michael B; McAllan, Bronwyn M

2018-02-05

Early pregnancy is a critical time for successful reproduction; up to half of human pregnancies fail before the development of the definitive chorioallantoic placenta. Unlike the situation in eutherian mammals, marsupial pregnancy is characterised by a long pre-implantation period prior to the development of the short-lived placenta, making them ideal models for study of the uterine environment promoting embryonic survival pre-implantation. Here we present a transcriptomic study of pre-implantation marsupial pregnancy, and identify differentially expressed genes in the Sminthopsis crassicaudata uterus involved in metabolism and biosynthesis, transport, immunity, tissue remodelling, and uterine receptivity. Interestingly, almost one quarter of the top 50 genes that are differentially upregulated in early pregnancy are putatively involved in histotrophy, highlighting the importance of nutrient transport to the conceptus prior to the development of the placenta. This work furthers our understanding of the mechanisms underlying survival of pre-implantation embryos in the earliest live bearing ancestors of mammals.

Preimplantation diagnosis of repeated miscarriage due to chromosomal translocations using metaphase chromosomes of a blastomere biopsied from 4- to 6-cell-stage embryos.

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Tanaka, Atsushi; Nagayoshi, Motoi; Awata, Shoichiro; Mawatari, Yoshifumi; Tanaka, Izumi; Kusunoki, Hiroshi

2004-01-01

To evaluate the safety and accuracy of karyotyping the blastomere chromosomes at metaphase in the natural cell cycle for preimplantation diagnosis. A pilot study. A private infertility clinic and a university laboratory. Eleven patients undergoing IVF and preimplantation diagnosis. Intact human embryos at the 4- to 6-cell stage and human-mouse heterokaryons were cultured and checked hourly for disappearance of the nuclear envelope. After it disappeared, the metaphase chromosomes were analyzed by fluorescence in situ hybridization. Percentage of analyzable metaphase plates and safety and accuracy of the method. The success rate of electrofusion to form human-mouse heterokaryons was 87.1% (27/31), and analyzable chromosomes were obtained from 77.4% (24/31) of the heterokaryons. On the other hand, disappearance of the nuclear envelope occurred in 89.5% (17/19) of the human embryos and it began earlier than that in the heterokaryons. Analyzable chromosomes were obtained and their translocation sites were identified in all blastomeres biopsied from the 17 embryos. After the biopsy, 67.0% of the embryos could develop to the blastocyst stage. The natural cell cycle method reported herein requires frequent observation, but it is safe, with no artificial effects on the chromosomes and without loss of or damage to blastomeres, which occurred with the electrofusion method. Using the natural cell cycle method, we could perform preimplantation diagnosis with nearly 100% accuracy.

Improving embryo quality in assisted reproduction

NARCIS (Netherlands)

Mantikou, E.

2013-01-01

The goal of this thesis was to improve embryo quality in assisted reproductive technologies by gaining more insight into human preimplantation embryo development and by improving in vitro culture conditions. To do so, we investigated an intriguing feature of the human preimplantation embryo, i.e.

Preimplantation Genetic Screening and Preimplantation Genetic Diagnosis.

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Sullivan-Pyke, Chantae; Dokras, Anuja

2018-03-01

Preimplantation genetic testing encompasses preimplantation genetic screening (PGS) and preimplantation genetic diagnosis (PGD). PGS improves success rates of in vitro fertilization by ensuring the transfer of euploid embryos that have a higher chance of implantation and resulting in a live birth. PGD enables the identification of embryos with specific disease-causing mutations and transfer of unaffected embryos. The development of whole genome amplification and genomic tools, including single nucleotide polymorphism microarrays, comparative genomic hybridization microarrays, and next-generation sequencing, has led to faster, more accurate diagnoses that translate to improved pregnancy and live birth rates. Copyright © 2017 Elsevier Inc. All rights reserved.

Can a genetically-modified organism-containing diet influence embryo development? A preliminary study on pre-implantation mouse embryos

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B Cisterna

2009-08-01

Full Text Available In eukaryotic cells, pre-mRNAs undergo several transformation steps to generate mature mRNAs. Recent studies have demonstrated that a diet containing a genetically modified (GM soybean can induce modifications of nuclear constituents involved in RNA processing in some tissues of young, adult and old mice. On this basis, we have investigated the ultrastructural and immunocytochemical features of pre-implantation embryos from mice fed either GM or non- GM soybean in order to verify whether the parental diet can affect the morpho-functional development of the embryonic ribonucleoprotein structural constituents involved in premRNA pathways. Morphological observations revealed that the general aspect of embryo nuclear components is similar in the two experimental groups. However, immunocytochemical and in situ hybridization results suggest a temporary decrease of pre-mRNA transcription and splicing in 2-cell embryos and a resumption in 4-8-cell embryos from mice fed GM soybean; moreover, pre-mRNA maturation seems to be less efficient in both 2-cell and 4-8-cell embryos from GM-fed mice than in controls. Although our results are still preliminary and limited to the pre-implantation phases, the results of this study encourage deepening on the effects of food components and/or contaminants on embryo development.

Can a genetically-modified organism-containing diet influence embryo development? A preliminary study on pre-implantation mouse embryos.

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Cisterna, B; Flach, F; Vecchio, L; Barabino, S M L; Battistelli, S; Martin, T E; Malatesta, M; Biggiogera, M

2008-01-01

In eukaryotic cells, pre-mRNAs undergo several transformation steps to generate mature mRNAs. Recent studies have demonstrated that a diet containing a genetically modified (GM) soybean can induce modifications of nuclear constituents involved in RNA processing in some tissues of young, adult and old mice. On this basis, we have investigated the ultrastructural and immunocytochemical features of pre-implantation embryos from mice fed either GM or non- GM soybean in order to verify whether the parental diet can affect the morpho-functional development of the embryonic ribonucleoprotein structural constituents involved in pre-mRNA pathways. Morphological observations revealed that the general aspect of embryo nuclear components is similar in the two experimental groups. However, immunocytochemical and in situ hybridization results suggest a temporary decrease of pre-mRNA transcription and splicing in 2-cell embryos and a resumption in 4-8-cell embryos from mice fed GM soybean; moreover, pre-mRNA maturation seems to be less efficient in both 2-cell and 4-8-cell embryos from GM-fed mice than in controls. Although our results are still preliminary and limited to the pre-implantation phases, the results of this study encourage deepening on the effects of food components and/or contaminants on embryo development.

The environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin disrupts morphogenesis of the rat pre-implantation embryo

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Albertini David F

2008-01-01

Full Text Available Abstract Background Environmental toxicants, whose actions are often mediated through the aryl hydrocarbon receptor (AhR pathway, pose risks to the health and well-being of exposed species, including humans. Of particular concern are exposures during the earliest stages of development that while failing to abrogate embryogenesis, may have long term effects on newborns or adults. The purpose of this study was to evaluate the effect of maternal exposure to the AhR-specific ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD on the development of rat pre-implantation embryos with respect to nuclear and cytoskeletal architecture and cell lineage allocation. Results We performed a systematic 3 dimensional (3D confocal microscopy analysis of rat pre-implantation embryos following maternal exposure to environmentally relevant doses of TCDD. Both chronic (50 ng/kg/wk for 3 months and acute (50 ng/kg and 1 μg/kg at proestrus maternal TCDD exposure disrupted morphogenesis at the compaction stage (8–16 cell, with defects including monopolar spindle formation, f-actin capping and fragmentation due to aberrant cytokinesis. Additionally, the size, shape and position of nuclei were modified in compaction stage pre-implantation embryos collected from treated animals. Notably, maternal TCDD exposure did not compromise survival to blastocyst, which with the exception of nuclear shape, were morphologically similar to control blastocysts. Conclusion We have identified the compaction stage of pre-implantation embryogenesis as critically sensitive to the effects of TCDD, while survival to the blastocyst stage is not compromised. To the best of our knowledge this is the first in vivo study to demonstrate a critical window of pre-implantation mammalian development that is vulnerable to disruption by an AhR ligand at environmentally relevant doses.

What next for preimplantation genetic screening? A polar body approach!

NARCIS (Netherlands)

Geraedts, Joep; Collins, John; Gianaroli, Luca; Goossens, Veerle; Handyside, Alan; Harper, Joyce; Montag, Markus; Repping, Sjoerd; Schmutzler, Andreas

2010-01-01

Screening of human preimplantation embryos for numerical chromosome abnormalities has been conducted mostly at the preimplantation stage using fluorescence in situ hybridization. However, it is clear that preimplantation genetic screening (PGS) as it is currently practiced does not improve live

Advances in preimplantation genetic diagnosis/screening.

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Yan, LiYing; Wei, Yuan; Huang, Jin; Zhu, XiaoHui; Shi, XiaoDan; Xia, Xi; Yan, Jie; Lu, CuiLing; Lian, Ying; Li, Rong; Liu, Ping; Qiao, Jie

2014-07-01

Preimplantation genetic diagnosis (PGD) gives couples who have a high risk of transmitting genetic disorders to their baby the chance to have a healthy offspring through embryo genetic analysis and selection. Preimplantation genetic screening (PGS) is an effective method to select euploid embryos that may prevent repeated implantation failure or miscarriage. However, how and to whom PGS should be provided is a controversial topic. The first successful case of PGD of a human being was reported in 1990, and there have been tremendous improvements in this technology since then. Both embryo biopsy and genetic technologies have been improved dramatically, which increase the accuracy and expand the indications of PGD/PGS.

Selection of reference genes for quantitative real-time PCR in bovine preimplantation embryos

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Van Zeveren Alex

2005-12-01

Full Text Available Abstract Background Real-time quantitative PCR is a sensitive and very efficient technique to examine gene transcription patterns in preimplantation embryos, in order to gain information about embryo development and to optimize assisted reproductive technologies. Critical to the succesful application of real-time PCR is careful assay design, reaction optimization and validation to maximize sensitivity and accuracy. In most of the studies published GAPD, ACTB or 18S rRNA have been used as a single reference gene without prior verification of their expression stability. Normalization of the data using unstable controls can result in erroneous conclusions, especially when only one reference gene is used. Results In this study the transcription levels of 8 commonly used reference genes (ACTB, GAPD, Histone H2A, TBP, HPRT1, SDHA, YWHAZ and 18S rRNA were determined at different preimplantation stages (2-cell, 8-cell, blastocyst and hatched blastocyst in order to select the most stable genes to normalize quantitative data within different preimplantation embryo stages. Conclusion Using the geNorm application YWHAZ, GAPD and SDHA were found to be the most stable genes across the examined embryonic stages, while the commonly used ACTB was shown to be highly regulated. We recommend the use of the geometric mean of those 3 reference genes as an accurate normalization factor, which allows small expression differences to be reliably measured.

Pro-apoptotic Effect of Pifithrin-α on Preimplantation Porcine Fertilized Embryo Development

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Brendan Mulligan

2012-12-01

Full Text Available The aim of this study was to investigate the impact of a reported p53 inhibitor, pifithrin-α (PFT-α, on preimplantation porcine in vitro fertilized (IVF embryo development in culture. Treatment of PFT-α was administered at both early (0 to 48 hpi, and later stages (48 to 168 hpi of preimplantation development, and its impact upon the expression of five genes related to apoptosis (p53, bak, bcl-xL, p66Shc and caspase3, was assessed in resulting d 7 blastocysts, using real-time quantitative PCR. Total cell numbers, along with the number of apoptotic nuclei, as detected by the in situ cell death detection assay, were also calculated on d 7 in treated and non-treated control embryos. The results indicate that PFT-α, when administered at both early and later stages of porcine IVF embryo development, increases the incidence of apoptosis in resulting blastocysts. When administered at early cleavage stages, PFT-α treatment was shown to reduce the developmental competence of porcine IVF embryos, as well as reducing the quality of resulting blastocysts in terms of overall cell numbers. In contrast, at later stages, PFT-α administration resulted in marginally increased blastocyst development rates amongst treated embryos, but did not affect cell numbers. However, PFT-α treatment induced apoptosis and apoptotic related gene expression, in all treated embryos, irrespective of the timing of treatment. Our results indicate that PFT-α may severely compromise the developmental potential of porcine IVF embryos, and is a potent apoptotic agent when placed into porcine embryo culture media. Thus, caution should be exercised when using PFT-α as a specific inhibitor of p53 mediated apoptosis, in the context of porcine IVF embryo culture systems.

[Current options of preimplantion genetic screening and preimplantation genetic diagnostics].

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Šimečková, V

The aim of this work is to summarize the current knowledge about preimplantation genetic screening and diagnostics. A review article. Department of Gynecology and Obstetrics, District Hospital Šternberk, IVF Clinic, Olomouc. Preimplantation genetic testing is a complex of genetic and molecular cytogenetic examinations, which can help to detect abnormalities in embryos before transfer into the uterus of the mother. These specialized examinations are based on the latest findings in genetics and assisted reproduction. The preimplantation genetic testing is necessarily associated with a method of in vitro fertilization. It is performed on isolated blastomeres on the third day of embryo cultivation. Nowadays, it is preferred trophectoderm examination of cells from the five-day blastocysts. Generally speaking, after preimplantation genetic testing, we can select only embryos without genetic load to transfer into uterus. Preimplantation genetic testing is an important part of treatment of infertility. Complex diagnostics and treatment of infertile couples are increasingly influenced by the development and use of advanced genomic technologies. Further development and application of these modern methods require close cooperation between the field of assisted reproduction and clinical genetics.

Maternal Diabetes Leads to Unphysiological High Lipid Accumulation in Rabbit Preimplantation Embryos

NARCIS (Netherlands)

Schindler, Maria; Pendzialek, Mareike; Santos, Alexander Navarrete; Ploesch, Torsten; Seyring, Stefanie; Guerke, Jacqueline; Haucke, Elisa; Knelangen, Julia Miriam; Fischer, Bernd; Santos, Anne Navarrete

According to the "developmental origin of health and disease" hypothesis, the metabolic set points of glucose and lipid metabolism are determined prenatally. In the case of a diabetic pregnancy, the embryo is exposed to higher glucose and lipid concentrations as early as during preimplantation

Expression and localization of heterogeneous nuclear ribonucleoprotein K in mouse ovaries and preimplantation embryos

International Nuclear Information System (INIS)

Zhang, Ping; Wang, Ningling; Lin, Xianhua; Jin, Li; Xu, Hong; Li, Rong; Huang, Hefeng

2016-01-01

Heterogeneous nuclear ribonucleoprotein K (hnRNP K), an evolutionarily conserved protein, is involved in several important cellular processes that are relevant to cell proliferation, differentiation, apoptosis, and cancer development. However, details of hnRNP K expression during mammalian oogenesis and preimplantation embryo development are lacking. The present study investigates the expression and cellular localization of K protein in the mouse ovaries and preimplantation embryos using immunostaining. We demonstrate, for the first time, that hnRNP K is abundantly expressed in the nuclei of mouse oocytes in primordial, primary and secondary follicles. In germ vesicle (GV)-stage oocytes, hnRNP K accumulates in the germinal vesicle in a spot distribution manner. After germinal vesicle breakdown, speckled hnRNP K is diffusely distributed in the cytoplasm. However, after fertilization, the K protein relocates into the female and male pronucleus and persists in the blastomere nuclei. Localization of K protein in the human ovary and ovarian granulosa cell tumor (GCT) was also investigated. Overall, this study provides important morphological evidence to better understand the possible roles of hnRNP K in mammalian oogenesis and early embryo development. - Highlights: • HnRNP K localizes in the nucleus of GV-stage oocyte in a punctate distribution. • HnRNP K strongly accumulates in zygotic pronuclei as condensed spots. • The localization of hnRNP K during oogenesis and embryogenesis is characteristic. • HnRNP K might have an important role in oogenesis and embryonic development.

Expression and localization of heterogeneous nuclear ribonucleoprotein K in mouse ovaries and preimplantation embryos

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Zhang, Ping [The International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai (China); Wang, Ningling [Department of Assisted Reproduction, Shanghai Ninth People' s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai (China); Lin, Xianhua; Jin, Li [The International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai (China); Xu, Hong, E-mail: xuhong1168@126.com [The International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai (China); Li, Rong [The International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai (China); Huang, Hefeng, E-mail: huanghefg@hotmail.com [The International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai (China)

2016-02-26

Heterogeneous nuclear ribonucleoprotein K (hnRNP K), an evolutionarily conserved protein, is involved in several important cellular processes that are relevant to cell proliferation, differentiation, apoptosis, and cancer development. However, details of hnRNP K expression during mammalian oogenesis and preimplantation embryo development are lacking. The present study investigates the expression and cellular localization of K protein in the mouse ovaries and preimplantation embryos using immunostaining. We demonstrate, for the first time, that hnRNP K is abundantly expressed in the nuclei of mouse oocytes in primordial, primary and secondary follicles. In germ vesicle (GV)-stage oocytes, hnRNP K accumulates in the germinal vesicle in a spot distribution manner. After germinal vesicle breakdown, speckled hnRNP K is diffusely distributed in the cytoplasm. However, after fertilization, the K protein relocates into the female and male pronucleus and persists in the blastomere nuclei. Localization of K protein in the human ovary and ovarian granulosa cell tumor (GCT) was also investigated. Overall, this study provides important morphological evidence to better understand the possible roles of hnRNP K in mammalian oogenesis and early embryo development. - Highlights: • HnRNP K localizes in the nucleus of GV-stage oocyte in a punctate distribution. • HnRNP K strongly accumulates in zygotic pronuclei as condensed spots. • The localization of hnRNP K during oogenesis and embryogenesis is characteristic. • HnRNP K might have an important role in oogenesis and embryonic development.

Proof of concept: preimplantation genetic screening without embryo biopsy through analysis of cell-free DNA in spent embryo culture media.

Science.gov (United States)

Shamonki, Mousa I; Jin, Helen; Haimowitz, Zachary; Liu, Lian

2016-11-01

To assess whether preimplantation genetic screening (PGS) is possible by testing for free embryonic DNA in spent IVF media from embryos undergoing trophectoderm biopsy. Prospective cohort analysis. Academic fertility center. Seven patients undergoing IVF and 57 embryos undergoing trophectoderm biopsy for PGS. On day 3 of development, each embryo was placed in a separate media droplet. All biopsied embryos received a PGS result by array comparative genomic hybridization. Preimplantation genetic screening was performed on amplified DNA extracted from media and results were compared with PGS results for the corresponding biopsy. [1] Presence of DNA in spent IVF culture media. [2] Correlation between genetic screening result from spent media and corresponding biopsy. Fifty-five samples had detectable DNA ranging from 2-642 ng/μL after a 2-hour amplification. Six samples with the highest DNA levels underwent PGS, rendering one result with a derivative log ratio SD (DLRSD) of media and a result that is consistent with trophectoderm biopsy. Improvements in DNA collection, amplification, and testing may allow for PGS without biopsy in the future. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Novel technologies emerging for preimplantation genetic diagnosis and preimplantation genetic testing for aneuploidy.

Science.gov (United States)

Sermon, Karen

2017-01-01

Preimplantation genetic diagnosis (PGD) was introduced as an alternative to prenatal diagnosis: embryos cultured in vitro were analysed for a monogenic disease and only disease-free embryos were transferred to the mother, to avoid the termination of pregnancy with an affected foetus. It soon transpired that human embryos show a great deal of acquired chromosomal abnormalities, thought to explain the low success rate of IVF - hence preimplantation genetic testing for aneuploidy (PGT-A) was developed to select euploid embryos for transfer. Areas covered: PGD has followed the tremendous evolution in genetic analysis, with only a slight delay due to adaptations for diagnosis on small samples. Currently, next generation sequencing combining chromosome with single-base pair analysis is on the verge of becoming the golden standard in PGD and PGT-A. Papers highlighting the different steps in the evolution of PGD/PGT-A were selected. Expert commentary: Different methodologies used in PGD/PGT-A with their pros and cons are discussed.

Preimplantation Genetic Diagnosis: Prenatal Testing for Embryos Finally Achieving Its Potential

Directory of Open Access Journals (Sweden)

Harvey J. Stern

2014-03-01

Full Text Available Preimplantation genetic diagnosis was developed nearly a quarter-century ago as an alternative form of prenatal diagnosis that is carried out on embryos. Initially offered for diagnosis in couples at-risk for single gene genetic disorders, such as cystic fibrosis, spinal muscular atrophy and Huntington disease, preimplantation genetic diagnosis (PGD has most frequently been employed in assisted reproduction for detection of chromosome aneuploidy from advancing maternal age or structural chromosome rearrangements. Major improvements have been seen in PGD analysis with movement away from older, less effective technologies, such as fluorescence in situ hybridization (FISH, to newer molecular tools, such as DNA microarrays and next generation sequencing. Improved results have also started to be seen with decreasing use of Day 3 blastomere biopsy in favor of polar body or Day 5 trophectoderm biopsy. Discussions regarding the scientific, ethical, legal and social issues surrounding the use of sequence data from embryo biopsy have begun and must continue to avoid concern regarding eugenic or inappropriate use of this technology.

Preimplantation Genetic Diagnosis: Prenatal Testing for Embryos Finally Achieving Its Potential

Science.gov (United States)

Stern, Harvey J.

2014-01-01

Preimplantation genetic diagnosis was developed nearly a quarter-century ago as an alternative form of prenatal diagnosis that is carried out on embryos. Initially offered for diagnosis in couples at-risk for single gene genetic disorders, such as cystic fibrosis, spinal muscular atrophy and Huntington disease, preimplantation genetic diagnosis (PGD) has most frequently been employed in assisted reproduction for detection of chromosome aneuploidy from advancing maternal age or structural chromosome rearrangements. Major improvements have been seen in PGD analysis with movement away from older, less effective technologies, such as fluorescence in situ hybridization (FISH), to newer molecular tools, such as DNA microarrays and next generation sequencing. Improved results have also started to be seen with decreasing use of Day 3 blastomere biopsy in favor of polar body or Day 5 trophectoderm biopsy. Discussions regarding the scientific, ethical, legal and social issues surrounding the use of sequence data from embryo biopsy have begun and must continue to avoid concern regarding eugenic or inappropriate use of this technology. PMID:26237262

Preimplantation genetic screening.

Science.gov (United States)

Harper, Joyce C

2018-03-01

Preimplantation genetic diagnosis was first successfully performed in 1989 as an alternative to prenatal diagnosis for couples at risk of transmitting a genetic or chromosomal abnormality, such as cystic fibrosis, to their child. From embryos generated in vitro, biopsied cells are genetically tested. From the mid-1990s, this technology has been employed as an embryo selection tool for patients undergoing in vitro fertilisation, screening as many chromosomes as possible, in the hope that selecting chromosomally normal embryos will lead to higher implantation and decreased miscarriage rates. This procedure, preimplantation genetic screening, was initially performed using fluorescent in situ hybridisation, but 11 randomised controlled trials of screening using this technique showed no improvement in in vitro fertilisation delivery rates. Progress in genetic testing has led to the introduction of array comparative genomic hybridisation, quantitative polymerase chain reaction, and next generation sequencing for preimplantation genetic screening, and three small randomised controlled trials of preimplantation genetic screening using these new techniques indicate a modest benefit. Other trials are still in progress but, regardless of their results, preimplantation genetic screening is now being offered globally. In the near future, it is likely that sequencing will be used to screen the full genetic code of the embryo.

Technique of the 'in vitro' fertilization and the culture of mouse embryos at preimplantation

International Nuclear Information System (INIS)

Kikuchi, Olivia Kimiko; Yamada, Takeshi

1993-03-01

The mammal embryo is an intensive cellular proliferating system, very radiosensitive and therefore adequate to the study of the biological effects of ionizing radiation. The technique of the in vitro fertilization and the culture of mouse embryos at preimplantation period, modified by Yamada et al (1982) to improve the efficiency of more than 95% of blastocyst formation is described. (author)

Meiotic and mitotic behaviour of a ring/deleted chromosome 22 in human embryos determined by preimplantation genetic diagnosis for a maternal carrier

Directory of Open Access Journals (Sweden)

Laver Sarah

2009-01-01

Full Text Available Abstract Background Ring chromosomes are normally associated with developmental anomalies and are rarely inherited. An exception to this rule is provided by deletion/ring cases. We were provided with a unique opportunity to investigate the meiotic segregation at oogenesis in a woman who is a carrier of a deleted/ring 22 chromosome. The couple requested preimplantation genetic diagnosis (PGD following the birth of a son with a mosaic karyotype. The couple underwent two cycles of PGD. Studies were performed on lymphocytes, single embryonic cells removed from 3 day-old embryos and un-transferred embryos. Analysis was carried out using fluorescence in situ hybridisation (FISH with specific probe sets in two rounds of hybridization. Results In total, 12 embryos were biopsied, and follow up information was obtained for 10 embryos. No embryos were completely normal or balanced for chromosome 22 by day 5. There was only one embryo diagnosed as balanced of 12 biopsied but that accumulated postzygotic errors by day 5. Three oocytes apparently had a balanced chromosome 22 complement but all had the deleted and the ring 22 and not the intact chromosome 22. After fertilisation all the embryos accumulated postzygotic errors for chromosome 22. Conclusion The study of the preimplantation embryos in this case provided a rare and significant chance to study and understand the phenomena associated with this unusual type of anomaly during meiosis and in the earliest stages of development. It is the first reported PGD attempt for a ring chromosome abnormality.

Active caspase-3 and ultrastructural evidence of apoptosis in spontaneous and induced cell death in bovine in vitro produced pre-implantation embryos

DEFF Research Database (Denmark)

Gjørret, Jakob O.; Fabian, Dusan; Avery, Birthe

2007-01-01

In this study we investigated chronological onset and involvement of active caspase-3, apoptotic nuclear morphology, and TUNEL-labeling, as well as ultrastructural evidence of apoptosis, in both spontaneous and induced cell death during pre-implantation development of bovine in vitro produced...... microscopy in both treated and untreated blastocysts. Activation of caspase-3 is likely involved in both spontaneous and induced apoptosis in bovine pre-implantation embryos, and immunohistochemical staining of active caspase-3 may be used in combination with other markers to identify apoptosis in pre...... embryos. Pre-implantation embryos (2-cell to Day 8 blastocysts) were cultured with either no supplementation (untreated) or with 10 µM staurosporine for 24 hr (treated). Embryos were subjected to immunohistochemical staining of active caspase-3, TUNEL-reaction for detection of DNA degradation and DAPI...

Preliminar toxicological assesement of Ruta graveolens, Origanum vulgare and Persea americana on the preimplantational mouse embryos

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V. Benavides

2014-06-01

Full Text Available The growing interest in natural medicine makes it necessary to study plant properties as well as their possible secondary effects. In recent years the toxic effects of many medicinal plants on the preimplantational mouse embryo development have been studied. Many of them produce malformations and alterations in the embryonic development. Ruta graveolens "ruda", Origanum vulgare "oregano" and Persea americana "palta" are used in rural areas to menstrual colic and to provoke abortion (estrella, 1995. This study is aimed at assessing "in vivd'the effect of extracts of "oregano", "ruda" and "palta" to 20% on the morphology and growth of preimplantational mouse embryos.

Site-specific modification of genome with cell-permeable Cre fusion protein in preimplantation mouse embryo

International Nuclear Information System (INIS)

Kim, Kyoungmi; Kim, Hwain; Lee, Daekee

2009-01-01

Site-specific recombination (SSR) by Cre recombinase and its target sequence, loxP, is a valuable tool in genetic analysis of gene function. Recently, several studies reported successful application of Cre fusion protein containing protein transduction peptide for inducing gene modification in various mammalian cells including ES cell as well as in the whole animal. In this study, we show that a short incubation of preimplantation mouse embryos with purified cell-permeable Cre fusion protein results in efficient SSR. X-Gal staining of preimplantation embryos, heterozygous for Gtrosa26 tm1Sor , revealed that treatment of 1-cell or 2-cell embryos with 3 μM of Cre fusion protein for 2 h leads to Cre-mediated excision in 70-85% of embryos. We have examined the effect of the concentration of the Cre fusion protein and the duration of the treatment on embryonic development, established a condition for full term development and survival to adulthood, and demonstrated the germ line transmission of excised Gtrosa26 allele. Potential applications and advantages of the highly efficient technique described here are discussed.

Enzymatic amplification of a Y chromosome repeat in a single blastomere allows identification of the sex of preimplantation mouse embryos

International Nuclear Information System (INIS)

Bradbury, M.W.; Isola, L.M.; Gordon, J.W.

1990-01-01

The polymerase chain reaction (PCR) technique has been adapted to identify the sex of preimplantation mouse embryos rapidly. PCR was used to amplify a specific repeated DNA sequence on the Y chromosome from a single isolated blastomere in under 12 hr. The remainder of the biopsied embryo was then transferred to a pseudopregnant female and carried to term. Using this technique, 72% of embryos can be classed as potentially either male or female. Transfers of such embryos have produced pregnancies with 8/8 fetuses (100%) being of the predicted sex. Variations of the technique have demonstrated certain limitations to the present procedure as well as indicated possible strategies for improvement of the assay. The PCR technique may have wide application in the genetic analysis of preimplantation embryos

Insulin-like growth factor-1 protects preimplantation embryos from anti-developmental actions of menadione.

Science.gov (United States)

Moss, James I; Pontes, Eduardo; Hansen, Peter James

2009-11-01

Menadione is a naphthoquinone used as a vitamin K source in animal feed that can generate reactive oxygen species (ROS) and cause apoptosis. Here, we examined whether menadione reduces development of preimplantation bovine embryos in a ROS-dependent process and tested the hypothesis that actions of menadione would be reduced by insulin-like growth factor-1 (IGF-1). Menadione caused a concentration-dependent decrease in the proportion of embryos that became blastocysts. All concentrations tested (1, 2.5, and 5.0 microM) inhibited development. Treatment with 100 ng/ml IGF-1 reduced the magnitude of the anti-developmental effects of the two lowest menadione concentrations. Menadione also caused a concentration-dependent increase in the percent of cells positive for the TUNEL reaction. The response was lower for IGF-1-treated embryos. The effects of menadione were mediated by ROS because (1) the anti-developmental effect of menadione was blocked by the antioxidants dithiothreitol and Trolox and (2) menadione caused an increase in ROS generation. Treatment with IGF-1 did not reduce ROS formation in menadione-treated embryos. In conclusion, concentrations of menadione as low as 1.0 muM can compromise development of bovine preimplantation embryos to the blastocyst stage of development in a ROS-dependent mechanism. Anti-developmental actions of menadione can be blocked by IGF-1 through effects downstream of ROS generation.

Effect of increased urea levels on mouse preimplantation embryos develop in vivo and in vitro

Czech Academy of Sciences Publication Activity Database

Bystriansky, J.; Burkuš, J.; Juhás, Štefan; Fabian, D.; Koppel, J.

2012-01-01

Roč. 56, č. 2 (2012), s. 211-216 ISSN 0042-4870 Institutional support: RVO:67985904 Keywords : mouse * preimplantation embryo * urea Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 0.377, year: 2012

Minute changes to the culture environment of mouse pre-implantation embryos affect the health of the conceptus

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George Koustas

2016-07-01

Conclusions: Exposing mouse pre-implantation embryos to ambient air at 37.0 °C, even for brief periods for routine micromanipulations is detrimental to normal embryonic development. Our results highlight the importance of how small alterations in the culture environment can have major consequences for the health of the embryo.

The future (r)evolution of preimplantation genetic diagnosis/human leukocyte antigen testing: ethical reflections.

Science.gov (United States)

de Wert, Guido; Liebaers, Inge; Van de Velde, Hilde

2007-09-01

There has been increasing support for combining preimplantation genetic diagnosis (PGD) for specific diseases with a test for human leukocyte antigens (HLA) because the generation of HLA-matched umbilical cord blood cells may save the life of a diseased sibling. To date, this procedure has taken place in the context of conceiving another child--PGD/HLA testing type 1. However, it may well become possible to perform PGD/HLA testing outside this context, that is, to select matched embryos from which embryonic stem cells could be derived and used in cell therapy--PGD/HLA testing type 2. A proactive ethical analysis is needed and is presented in this article. Although PGD/HLA testing type 1 can be morally justified, the risks, pitfalls, and practical limitations of this procedure make it necessary to develop alternative strategies. PGD/HLA testing type 2 may provide an alternative strategy. From an ethical point of view, the controversial issue is that this procedure creates embryos purely for instrumental use. However, given the dominant view that the preimplantation embryo has only limited moral value, this alternative may be as morally justified as PGD/HLA testing type 1.

Tripolar chromosome segregation drives the association between maternal genotype at variants spanning PLK4 and aneuploidy in human preimplantation embryos.

Science.gov (United States)

McCoy, Rajiv C; Newnham, Louise J; Ottolini, Christian S; Hoffmann, Eva R; Chatzimeletiou, Katerina; Cornejo, Omar E; Zhan, Qiansheng; Zaninovic, Nikica; Rosenwaks, Zev; Petrov, Dmitri A; Demko, Zachary P; Sigurjonsson, Styrmir; Handyside, Alan H

2018-04-24

Aneuploidy is prevalent in human embryos and is the leading cause of pregnancy loss. Many aneuploidies arise during oogenesis, increasing with maternal age. Superimposed on these meiotic aneuploidies are frequent errors occurring during early mitotic divisions, contributing to widespread chromosomal mosaicism. Here we reanalyzed a published dataset comprising preimplantation genetic testing for aneuploidy in 24,653 blastomere biopsies from day-3 cleavage-stage embryos, as well as 17,051 trophectoderm biopsies from day-5 blastocysts. We focused on complex abnormalities that affected multiple chromosomes simultaneously, seeking insights into their formation. In addition to well-described patterns such as triploidy and haploidy, we identified 4.7% of blastomeres possessing characteristic hypodiploid karyotypes. We inferred this signature to have arisen from tripolar chromosome segregation in normally-fertilized diploid zygotes or their descendant diploid cells. This could occur via segregation on a tripolar mitotic spindle or by rapid sequential bipolar mitoses without an intervening S-phase. Both models are consistent with time-lapse data from an intersecting set of 77 cleavage-stage embryos, which were enriched for the tripolar signature among embryos exhibiting abnormal cleavage. The tripolar signature was strongly associated with common maternal genetic variants spanning the centrosomal regulator PLK4, driving the association we previously reported with overall mitotic errors. Our findings are consistent with the known capacity of PLK4 to induce tripolar mitosis or precocious M-phase upon dysregulation. Together, our data support tripolar chromosome segregation as a key mechanism generating complex aneuploidy in cleavage-stage embryos and implicate maternal genotype at a quantitative trait locus spanning PLK4 as a factor influencing its occurrence.

Killing of preimplantation mouse embryos by main ingredients of cleansers AS and LAS

International Nuclear Information System (INIS)

Nomura, T.; Hata, S.; Shibata, K.; Kusafuka, T.

1987-01-01

When main ingredients of cleansers, alcohol sulfate (AS) and linear alkylbenzene sulfonate (LAS), were applied to the dorsal skin of pregnant JCL:ICR mice during preimplantation period, significant numbers of embryos collected from the oviducts and uteri on day 3 showed severe deformity or remained at the morula stage. Most of abnormal embryos were fragmented or remained at the 1-8 cell stages, and they were either dead or dying. Similar results were observed with commercially obtained kitchen detergent and hair shampoo. Fertilized eggs may be specifically sensitive to synthetic detergents. Very low doses of X-rays also induced significant yields of abnormal embryos. Major difference between X-rays and detergents was that X-ray-induced abnormality appeared at the morula or blastocyst stage, while detergent-induced one did at the earlier stages. (Auth.)

Preimplantation genetic haplotyping a new application for diagnosis of translocation carrier's embryos- preliminary observations of two robertsonian translocation carrier families.

Science.gov (United States)

Shamash, Jana; Rienstein, Shlomit; Wolf-Reznik, Haike; Pras, Elon; Dekel, Michal; Litmanovitch, Talia; Brengauz, Masha; Goldman, Boleslav; Yonath, Hagith; Dor, Jehoshua; Levron, Jacob; Aviram-Goldring, Ayala

2011-01-01

Preimplantation genetic diagnosis using fluorescence in-situ hybridization (PGD-FISH) is currently the most common reproductive solution for translocation carriers. However, this technique usually does not differentiate between embryos carrying the balanced form of the translocation and those carrying the homologous normal chromosomes. We developed a new application of preimplantation genetic haplotyping (PGH) that can identify and distinguish between all forms of the translocation status in cleavage stage embryos prior to implantation. Polymorphic markers were used to identify and differentiate between the alleles that carry the translocation and those that are the normal homologous chromosomes. Embryos from two families of robertsonian translocation carriers were successfully analyzed using polymorphic markers haplotyping. Our preliminary results indicate that the PGH is capable of distinguishing between normal, balanced and unbalanced translocation carrier embryos. This method will improve PGD and will enable translocation carriers to avoid transmission of the translocation and the associated medical complications to offspring.

Clinical utilisation of a rapid low-pass whole genome sequencing technique for the diagnosis of aneuploidy in human embryos prior to implantation.

Science.gov (United States)

Wells, Dagan; Kaur, Kulvinder; Grifo, Jamie; Glassner, Michael; Taylor, Jenny C; Fragouli, Elpida; Munne, Santiago

2014-08-01

The majority of human embryos created using in vitro fertilisation (IVF) techniques are aneuploid. Comprehensive chromosome screening methods, applicable to single cells biopsied from preimplantation embryos, allow reliable identification and transfer of euploid embryos. Recently, randomised trials using such methods have indicated that aneuploidy screening improves IVF success rates. However, the high cost of testing has restricted the availability of this potentially beneficial strategy. This study aimed to harness next-generation sequencing (NGS) technology, with the intention of lowering the costs of preimplantation aneuploidy screening. Embryo biopsy, whole genome amplification and semiconductor sequencing. A rapid (cost only two-thirds that of the most widely used method for embryo aneuploidy detection. Validation involved blinded analysis of 54 cells from cell lines or biopsies from human embryos. Sensitivity and specificity were 100%. The method was applied clinically, assisting in the selection of euploid embryos in two IVF cycles, producing healthy children in both cases. The NGS approach was also able to reveal specified mutations in the nuclear or mitochondrial genomes in parallel with chromosome assessment. Interestingly, elevated mitochondrial DNA content was associated with aneuploidy (pcost diagnosis of aneuploidy in cells from human preimplantation embryos and is rapid enough to allow testing without embryo cryopreservation. The method described also has the potential to shed light on other aspects of embryo genetics of relevance to health and viability. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

The effect of herbicide BASTA 15 on the development of mouse preimplantation embryos in vivo and in vitro.

Science.gov (United States)

Fabian, D; Bystriansky, J; Burkuš, J; Rehák, P; Legáth, J; Koppel, J

2011-02-01

The aim of this study was to evaluate the possible effect of maternal poisoning by BASTA-15 on developmental capacities and quality of preimplantation embryos in a mouse model. During in vivo tests, fertilized mice were fed with various doses of BASTA-15 for several days. During in vitro tests, isolated embryos were cultured in a medium with the addition of herbicide or its main compound glufosinate ammonium. Stereomicroscopic evaluation of embryonic pools obtained from treated dams showed that BASTA-15 at dose 58 μl/kg bw negatively affected their ability to reach the blastocyst stage. Moreover, as shown by morphological evaluation, based on cell counting and cell death assay, even the application of herbicide at the lowest dose (approx. 1/100 LD50) had a negative effect on obtained embryo quality. In vitro tests proved the direct ability of BASTA-15 to negatively affect embryo growth and quality. On the other hand, the addition of glufosinate ammonium at equivalent concentrations (from 0.015 to 15 μg/ml) had almost no damaging effect on embryos. It was harmful only at very high doses. Results show that maternal intoxication with BASTA-15 might affect the development of preimplantation embryos and suggest that the responsibility for this effect lies probably not solely with glufosinate ammonium, but in combination with the herbicide's secondary compounds. Copyright © 2010 Elsevier Ltd. All rights reserved.

Effect of organically bound tritium (OBT) on pre-implantation mouse embryos in vitro

International Nuclear Information System (INIS)

Yamada, Takeshi; Ohyama, Harumi

1989-01-01

Effect of organically bound tritium (OBT), such as tritiated thymidine and tritium-labeled amino acids, on mouse preimplantation embryos was examined in vitro. Mouse zygotes fertilized in vitro (BC3F 1 eggs x ICR sperm) were cultured in the media containing OBT in various concentrations up to the blastocyst stage. The LD 50 in terms of tritium concentrations in the culture medium were determined by measuring tritium concentrations in the medium to inhibit 50 % of embryos to form blastocyst in vitro. Tritium activities in the embryos were measured at various times during culture of embryos at LD 50 concentration in order to estimate absorbed radiation dose in embryonic cells. The LD 50 values obtained indicate that OBT could inhibit the embryonic development 1000 times more effectively that tritiated water (HTO). However, differences in LD 50 values in terms of absorbed radiation dose between OBT and HTO is not so essential, and might be explained by localized spatial distribution of OBT within the cell. (author)

Effect of in vitro culture of human embryos on birthweight of newborns

NARCIS (Netherlands)

Dumoulin, John C.; Land, Jolande A.; Van Montfoort, Aafke P.; Nelissen, Ewka C.; Coonen, Edith; Derhaag, Josien G.; Schreurs, Inge L.; Dunselman, Gerard A.; Kester, Arnold D.; Geraedts, Joep P.; Evers, Johannes L.

In animal models, in vitro culture of preimplantation embryos has been shown to be a risk factor for abnormal fetal outcome, including high and low birthweight. In the human, mean birthweight of singletons after in vitro fertilization (IVF) is considerably lower than after natural conception, but it

Polypeptide profiles of human oocytes and preimplantation embryos.

Science.gov (United States)

Capmany, G; Bolton, V N

1993-11-01

The polypeptides that direct fertilization and early development until activation of the embryonic genome occurs, at the 4-8 cell stage in the human, are exclusively maternal in origin, and are either synthesized during oogenesis or translated later from maternal mRNA. Using sodium dodecyl sulphate-polyacrylamide gel electrophoresis and silver stain, we have visualized and compared the polypeptides present in different populations of human oocytes and cleavage stage embryos obtained after superovulation and insemination in vitro. Two polypeptide patterns were resolved, differing in the region of mol. wt 69 kDa. The distribution of these patterns showed no correlation with the ability of individual oocytes to achieve fertilization and develop normally to the 8-cell stage.

Potential of human twin embryos generated by embryo splitting in assisted reproduction and research.

Science.gov (United States)

Noli, Laila; Ogilvie, Caroline; Khalaf, Yacoub; Ilic, Dusko

2017-03-01

Embryo splitting or twinning has been widely used in veterinary medicine over 20 years to generate monozygotic twins with desirable genetic characteristics. The first human embryo splitting, reported in 1993, triggered fierce ethical debate on human embryo cloning. Since Dolly the sheep was born in 1997, the international community has acknowledged the complexity of the moral arguments related to this research and has expressed concerns about the potential for reproductive cloning in humans. A number of countries have formulated bans either through laws, decrees or official statements. However, in general, these laws specifically define cloning as an embryo that is generated via nuclear transfer (NT) and do not mention embryo splitting. Only the UK includes under cloning both embryo splitting and NT in the same legislation. On the contrary, the Ethics Committee of the American Society for Reproductive Medicine does not have a major ethical objection to transferring two or more artificially created embryos with the same genome with the aim of producing a single pregnancy, stating that 'since embryo splitting has the potential to improve the efficacy of IVF treatments for infertility, research to investigate the technique is ethically acceptable'. Embryo splitting has been introduced successfully to the veterinary medicine several decades ago and today is a part of standard practice. We present here an overview of embryo splitting experiments in humans and non-human primates and discuss the potential of this technology in assisted reproduction and research. A comprehensive literature search was carried out using PUBMED and Google Scholar databases to identify studies on embryo splitting in humans and non-human primates. 'Embryo splitting' and 'embryo twinning' were used as the keywords, alone or in combination with other search phrases relevant to the topics of biology of preimplantation embryos. A very limited number of studies have been conducted in humans and non-human

First systematic experience of preimplantation genetic diagnosis for single-gene disorders, and/or preimplantation human leukocyte antigen typing, combined with 24-chromosome aneuploidy testing.

Science.gov (United States)

Rechitsky, Svetlana; Pakhalchuk, Tatiana; San Ramos, Geraldine; Goodman, Adam; Zlatopolsky, Zev; Kuliev, Anver

2015-02-01

To study the feasibility, accuracy, and reproductive outcome of 24-chromosome aneuploidy testing (24-AT), combined with preimplantation genetic diagnosis (PGD) for single-gene disorders (SGDs) or human leukocyte antigen (HLA) typing in the same biopsy sample. Retrospective study. Preimplantation genetic diagnosis center. A total of 238 PGD patients, average age 36.8 years, for whom 317 combined PGD cycles were performed, involving 105 different conditions, with or without HLA typing. Whole-genome amplification product, obtained in 24-AT, was used for PGD and/or HLA typing in the same blastomere or blastocyst biopsy samples. Proportion of the embryos suitable for transfer detected in these blastomere or blastocyst samples, and the resulting pregnancy and spontaneous abortion rates. Embryos suitable for transfer were detected in 42% blastocyst and 25.1% blastomere samples, with a total of 280 unaffected, HLA-matched euploid embryos detected for transfer in 212 cycles (1.3 embryos per transfer), resulting in 145 (68.4%) unaffected pregnancies and birth of 149 healthy, HLA-matched children. This outcome is significantly different from that of our 2,064 PGD cycle series without concomitant 24-AT, including improved pregnancy (68.4% vs. 45.4%) and 3-fold spontaneous abortion reduction (5.5% vs. 15%) rates. The introduced combined approach is a potential universal PGD test, which in addition to achieving extremely high diagnostic accuracy, significantly improves reproductive outcomes of PGD for SGDs and HLA typing in patients of advanced reproductive age. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Biopsy of human morula-stage embryos: outcome of 215 IVF/ICSI cycles with PGS.

Directory of Open Access Journals (Sweden)

Elena E Zakharova

Full Text Available Preimplantation genetic diagnosis (PGD is commonly performed on biopsies from 6-8-cell-stage embryos or blastocyst trophectoderm obtained on day 3 or 5, respectively. Day 4 human embryos at the morula stage were successfully biopsied. Biopsy was performed on 709 morulae from 215 ICSI cycles with preimplantation genetic screening (PGS, and 3-7 cells were obtained from each embryo. The most common vital aneuploidies (chromosomes X/Y, 21 were screened by fluorescence in situ hybridization (FISH. No aneuploidy was observed in 72.7% of embryos, 91% of those developed to blastocysts. Embryos were transferred on days 5-6. Clinical pregnancy was obtained in 32.8% of cases, and 60 babies were born. Patients who underwent ICSI/PGS treatment were compared with those who underwent standard ICSI treatment by examining the percentage of blastocysts, pregnancy rate, gestational length, birth height and weight. No significant differences in these parameters were observed between the groups. Day 4 biopsy procedure does not adversely affect embryo development in vitro or in vivo. The increased number of cells obtained by biopsy of morulae might facilitate diagnostic screening. There is enough time after biopsy to obtain PGD results for embryo transfer on day 5-6 in the current IVF cycle.

Insulin and branched-chain amino acid depletion during mouse preimplantation embryo culture programmes body weight gain and raised blood pressure during early postnatal life.

Science.gov (United States)

Velazquez, Miguel A; Sheth, Bhavwanti; Smith, Stephanie J; Eckert, Judith J; Osmond, Clive; Fleming, Tom P

2018-02-01

Mouse maternal low protein diet exclusively during preimplantation development (Emb-LPD) is sufficient to programme altered growth and cardiovascular dysfunction in offspring. Here, we use an in vitro model comprising preimplantation culture in medium depleted in insulin and branched-chain amino acids (BCAA), two proposed embryo programming inductive factors from Emb-LPD studies, to examine the consequences for blastocyst organisation and, after embryo transfer (ET), postnatal disease origin. Two-cell embryos were cultured to blastocyst stage in defined KSOM medium supplemented with four combinations of insulin and BCAA concentrations. Control medium contained serum insulin and uterine luminal fluid amino acid concentrations (including BCAA) found in control mothers from the maternal diet model (N-insulin+N-bcaa). Experimental medium (three groups) contained 50% reduction in insulin and/or BCAA (L-insulin+N-bcaa, N-insulin+L-bcaa, and L-insulin+N-bcaa). Lineage-specific cell numbers of resultant blastocysts were not affected by treatment. Following ET, a combined depletion of insulin and BCAA during embryo culture induced a non sex-specific increase in birth weight and weight gain during early postnatal life. Furthermore, male offspring displayed relative hypertension and female offspring reduced heart/body weight, both characteristics of Emb-LPD offspring. Combined depletion of metabolites also resulted in a strong positive correlation between body weight and glucose metabolism that was absent in the control group. Our results support the notion that composition of preimplantation culture medium can programme development and associate with disease origin affecting postnatal growth and cardiovascular phenotypes and implicate two important nutritional mediators in the inductive mechanism. Our data also have implications for human assisted reproductive treatment (ART) practice. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Preimplantation maternal stress impairs embryo development by inducing oviductal apoptosis with activation of the Fas system.

Science.gov (United States)

Zheng, Liang-Liang; Tan, Xiu-Wen; Cui, Xiang-Zhong; Yuan, Hong-Jie; Li, Hong; Jiao, Guang-Zhong; Ji, Chang-Li; Tan, Jing-He

2016-11-01

What are the mechanisms by which the preimplantation restraint stress (PIRS) impairs embryo development and pregnancy outcome? PIRS impairs embryo development by triggering apoptosis in mouse oviducts and embryos,and this involves activation of the Fas system. Although it is known that the early stages of pregnancy are more vulnerable than later stages to prenatalstress, studies on the effect of preimplantation stress on embryo developmentare limited. Furthermore, the mechanisms by which psychological stress impairs embryo development are largely unknown. These issues are worth exploring using the mouse PIRS models because restraint of mice is an efficient experimental procedure developed for studies of psychogenic stress. Mice of Kunming strain, the generalized lymphoproliferative disorder (gld) mice with a germline mutation F273L in FasL in a C57BL/6J genomic background and the wild-type C57BL/6J mice were used. Female and male mice were used 8-10 weeks and 10-12 weeks after birth, respectively. Female mice showing vaginal plugs were paired by weight and randomly assigned to restraint treatments or as controls. For restraint treatment, an individual mouse was put in a micro-cage with food and water available. Control mice remained in their cages with food and water during the time treated females were stressed. Female mice were exposed to PIRS for 48 h starting from 16:00 on the day of vaginal plug detection. At the end of PIRS, levels of glucorticoids (GC), corticotropin-releasing hormone (CRH)and redox potential were measured in serum, while levels of GC, GC receptor (GR), CRH, CRH receptor (CRHR), Fas and Fas ligand (FasL) protein, mRNAs for brain derived neurotrophic factor (BDNF) and insulin-like growth factor-1 (IGF-1), oxidative stress (OS) and apoptosis were examined in oviducts. Preimplantation development and levels of GR, Fas, redox potential and apoptosis were observed in embryos recovered at different times after the initiation of PIRS. The gld mice

Pregnancy after preimplantation diagnosis for a deletion in the dystrophin gene by polymerase chain reaction in embryos obtained after intracytoplasmic sperm injection

Energy Technology Data Exchange (ETDEWEB)

Lissens, W.; Liu, J.; Van Broeckhoven, C. [University Hospital, Brussels (Belgium)] [and others

1994-09-01

Duchenne muscular dystrophy (DMD) is one of the most common X-linked recessive diseases. In order to be able to perform a DMD-specific preimplantation diagnosis (PID) in a female carrier of a deletion of exons 3 to 18 in the dystrophin gene, we have developed a PCR assay to detect the deletion based on sequences of exon 17. The efficiency of this PCR was evaluated on 50 single blastomeres from 12 normal control embryos and on 41 blastomeres for 9 male and 3 female embryos from the female DMD carrier, obtained after a first preimplantation diagnosis by sexing. The exon 17 region was amplified with 100% efficiency, except in all 21 blastomeres from 6 male embryos from the carrier where no PCR signals were observed. The negative results in these blastomeres were interpreted as being found only in male embryos carrying the deletion. Intracytoplasmic sperm injection was carried out on the carrier`s metaphase II oocytes retrieved after ovarian stimulation. Embryos were analyzed for the presence of exon 17 and 2 male embryos were found to be deleted, while 4 embryos showed normal amplification signals. Three of the latter embryos were replaced, resulting in a singleton pregnancy. Amniotic cell analysis showed a normal female karyotype and DNA analysis indicated a non-carrier.

Clinical applications of preimplantation genetic testing.

Science.gov (United States)

Brezina, Paul R; Kutteh, William H

2015-02-19

Genetic diagnostic technologies are rapidly changing the way medicine is practiced. Preimplantation genetic testing is a well established application of genetic testing within the context of in vitro fertilization cycles. It involves obtaining a cell(s) from a developing embryo in culture, which is then subjected to genetic diagnostic analysis; the resulting information is used to guide which embryos are transferred into the uterus. The potential applications and use of this technology have increased in recent years. Experts agree that preimplantation genetic diagnosis is clinically appropriate for many known genetic disorders. However, some applications of such testing, such as preimplantation genetic screening for aneuploidy, remain controversial. Clinical data suggest that preimplantation genetic screening may be useful, but further studies are needed to quantify the size of the effect and who would benefit most. © BMJ Publishing Group Ltd 2015.

Where does New Zealand stand on permitting research on human embryos?

Science.gov (United States)

Jones, D Gareth

2014-08-01

In many respects New Zealand has responded to the assisted reproductive technologies (ARTs) as positively as many comparable societies, such as Australia and the UK. Consequently, in vitro fertilisation (IVF) and pre-implantation genetic diagnosis (PGD) are widely available, as is non-commercial surrogacy utilising IVF. These developments have been made possible by the Human Assisted Reproductive Technology (HART) Act 2004, overseen by its two committees, the Advisory Committee on Assisted Reproductive Technology (ACART) and the Ethics Committee (ECART). However, New Zealand stands apart from many of these other societies by the lack of permission for scientists to conduct research using human embryos. There is no doubt this reflects strongly held viewpoints on the part of some that embryos should be protected and not exploited. Legitimate as this stance is, the resulting situation is problematic when IVF is already designated as an established procedure. This is because the development of IVF involved embryo research, and continuing improvements in procedures depend upon ongoing embryo research. While prohibition of research on human embryos gives the impression of protecting embryos, it fails to do this and also fails to enhance the health and wellbeing of children born using IVF. This situation will not be rectified until research is allowed on human embryos.

New Advances of Preimplantation and Prenatal Genetic Screening and Noninvasive Testing as a Potential Predictor of Health Status of Babies

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Tanya Milachich

2014-01-01

Full Text Available The current morphologically based selection of human embryos for transfer cannot detect chromosome aneuploidies. So far, only biopsy techniques have been able to screen for chromosomal aneuploidies in the in vitro fertilization (IVF embryos. Preimplantation genetic diagnosis (PGD or screening (PGS involves the biopsy of oocyte polar bodies or embryonic cells and has become a routine clinical procedure in many IVF clinics worldwide, including recent development of comprehensive chromosome screening of all 23 pairs of chromosomes by microarrays for aneuploidy screening. The routine preimplantation and prenatal genetic diagnosis (PND require testing in an aggressive manner. These procedures may be invasive to the growing embryo and fetus and potentially could compromise the clinical outcome. Therefore the aim of this review is to summarize not only the new knowledge on preimplantation and prenatal genetic diagnosis in humans, but also on the development of potential noninvasive embryo and fetal testing that might play an important role in the future.

New Advances of Preimplantation and Prenatal Genetic Screening and Noninvasive Testing as a Potential Predictor of Health Status of Babies

Science.gov (United States)

2014-01-01

The current morphologically based selection of human embryos for transfer cannot detect chromosome aneuploidies. So far, only biopsy techniques have been able to screen for chromosomal aneuploidies in the in vitro fertilization (IVF) embryos. Preimplantation genetic diagnosis (PGD) or screening (PGS) involves the biopsy of oocyte polar bodies or embryonic cells and has become a routine clinical procedure in many IVF clinics worldwide, including recent development of comprehensive chromosome screening of all 23 pairs of chromosomes by microarrays for aneuploidy screening. The routine preimplantation and prenatal genetic diagnosis (PND) require testing in an aggressive manner. These procedures may be invasive to the growing embryo and fetus and potentially could compromise the clinical outcome. Therefore the aim of this review is to summarize not only the new knowledge on preimplantation and prenatal genetic diagnosis in humans, but also on the development of potential noninvasive embryo and fetal testing that might play an important role in the future. PMID:24783200

Whole Genome Amplification of Day 3 or Day 5 Human Embryos Biopsies Provides a Suitable DNA Template for PCR-Based Techniques for Genotyping, a Complement of Preimplantation Genetic Testing

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Elizabeth Schaeffer

2017-01-01

Full Text Available Our objective was to determine if whole genome amplification (WGA provides suitable DNA for qPCR-based genotyping for human embryos. Single blastomeres (Day 3 or trophoblastic cells (Day 5 were isolated from 342 embryos for WGA. Comparative Genomic Hybridization determined embryo sex as well as Trisomy 18 or Trisomy 21. To determine the embryo’s sex, qPCR melting curve analysis for SRY and DYS14 was used. Logistic regression indicated a 4.4%, 57.1%, or 98.8% probability of a male embryo when neither gene, SRY only, or both genes were detected, respectively (accuracy = 94.1%, kappa = 0.882, and p<0.001. Fluorescent Capillary Electrophoresis for the amelogenin genes (AMEL was also used to determine sex. AMELY peak’s height was higher and this peak’s presence was highly predictive of male embryos (AUC = 0.93, accuracy = 81.7%, kappa = 0.974, and p<0.001. Trisomy 18 and Trisomy 21 were determined using the threshold cycle difference for RPL17 and TTC3, respectively, which were significantly lower in the corresponding embryos. The Ct difference for TTC3 specifically determined Trisomy 21 (AUC = 0.89 and RPL17 for Trisomy 18 (AUC = 0.94. Here, WGA provides adequate DNA for PCR-based techniques for preimplantation genotyping.

Protein degradation in preimplantation mouse embryos and the lethality of tritiated amino acids

International Nuclear Information System (INIS)

Wielbold, J.L.

1982-01-01

The role of protein degradation in preimplantation development in the mouse was studied. Proteins of morulae and blastocysts (M and B) cultured in vitro after labeling for 1 hour (h) in 3 H-leucine exhibit a mean half-life (t 1 / 2 ) of 8.1 h. The t 1 / 2 tends to increase (9.5 h) when 10% fetal calf serum is added to the chase medium. This decrease in protein degradation in the presence of serum is associated with an increase in the percentage of B that are hatching (P 3 H-leucine in their proteins than did Day 4 embryos remaining in culture (P<0.02), while Day 4 embryos in a Day 3 uterus retained the same amount of radioactivity as did Day 4 embryos in culture. This differential effect of uterine environment was also seen when Day 4 embryos were transferred to recipients. More fetuses developed to term when the recipient was in Day 3 of PSP (50.8%) than when the recipient was in Day 4 PSP (25.9%, P<0.001), regardless of the age of the recipient. Age of the recipient does affect the percentage of transferred embryos developing to term. Thus, protein degradation may vary with the stage of embryo development and the conditions to which the embryos are exposed. However, even low levels of incorporated tritiated leucine can have lethal effects on the embryos and compromise the validity of the protein half-lives determined

Estimating limits for natural human embryo mortality [version 2; referees: 2 approved

Directory of Open Access Journals (Sweden)

Gavin E. Jarvis

2016-12-01

Full Text Available Natural human embryonic mortality is generally considered to be high. Values of 70% and higher are widely cited. However, it is difficult to determine accurately owing to an absence of direct data quantifying embryo loss between fertilisation and implantation. The best available data for quantifying pregnancy loss come from three published prospective studies (Wilcox, Zinaman and Wang with daily cycle by cycle monitoring of human chorionic gonadotrophin (hCG in women attempting to conceive. Declining conception rates cycle by cycle in these studies indicate that a proportion of the study participants were sub-fertile. Hence, estimates of fecundability and pre-implantation embryo mortality obtained from the whole study cohort will inevitably be biased. This new re-analysis of aggregate data from these studies confirms the impression that discrete fertile and sub-fertile sub-cohorts were present. The proportion of sub-fertile women in the three studies was estimated as 28.1% (Wilcox, 22.8% (Zinaman and 6.0% (Wang. The probability of conceiving an hCG pregnancy (indicating embryo implantation was, respectively, 43.2%, 38.1% and 46.2% among normally fertile women, and 7.6%, 2.5% and 4.7% among sub-fertile women. Pre-implantation loss is impossible to calculate directly from available data although plausible limits can be estimated. Based on this new analysis and a model for evaluating reproductive success and failure it is proposed that a plausible range for normal human embryo and fetal mortality from fertilisation to birth is 40-60%.

Raman spectroscopy analysis of differences in composition of spent culture media of in vitro cultured preimplantation embryos isolated from normal and fat mice dams.

Science.gov (United States)

Fabian, Dušan; Kačmarová, Martina; Kubandová, Janka; Čikoš, Štefan; Koppel, Juraj

2016-06-01

The aim of the present study was to compare overall patterns of metabolic activity of in vitro cultured preimplantation embryos isolated from normal and fat mice dams by means of non-invasive profiling of spent culture media using Raman spectroscopy. To produce females with two different types of body condition (normal and fat), a previously established two-generation model was used, based on overfeeding of experimental mice during prenatal and early postnatal development. Embryos were isolated from spontaneously ovulating and naturally fertilized dams at the 2-cell stage of development and cultured to the blastocyst stage in synthetic oviductal medium KSOMaa. Embryos from fat mice (displaying significantly elevated body weight and fat) showed similar developmental capabilities in vitro as embryos isolated from normal control dams (displaying physiological body weight and fat). The results show that alterations in the composition of culture medium caused by the presence of developing mouse preimplantation embryos can be detected using Raman spectroscopy. Metabolic activity of embryos was reflected in evident changes in numerous band intensities in the 1620-1690cm(-1) (amide I) region and in the 1020-1140cm(-1) region of the Raman spectrum for KSOMaa. Moreover, multivariate analysis of spectral data proved that the composition of proteins and other organic compounds in spent samples obtained after the culture of embryos isolated from fat dams was different from that in spent samples obtained after the culture of embryos from control dams. This study demonstrates that metabolic activity of cultured preimplantation embryos might depend on the body condition of their donors. Copyright © 2016 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Cell membrane and cell junctions in differentiation of preimplanted mouse embryos.

Science.gov (United States)

Izquierdo, L; Fernández, S; López, T

1976-12-01

Cell membrane and cell junctions in differentiation of preimplanted mouse embryos, (membrana celular y uniones celulares en la diferenciación del embrión de ratón antes de la implantación). Arch. Biol. Med. Exper. 10: 130-134, 1976. The development of cell junctions that seal the peripheral blastomeres could be a decisive step in the differentiation of morulae into blastocysts. The appearance of these junctions is studied by electron microscopy of late morulae and initial blastocysts. Zonulae occludentes as well as impermeability to lanthanum emulsion precedes the appearance of the blastocel and hence might be considered as one of its necessary causes.

Tripolar mitosis and partitioning of the genome arrests human preimplantation development in vitro.

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Ottolini, Christian S; Kitchen, John; Xanthopoulou, Leoni; Gordon, Tony; Summers, Michael C; Handyside, Alan H

2017-08-29

Following in vitro fertilisation (IVF), only about half of normally fertilised human embryos develop beyond cleavage and morula stages to form a blastocyst in vitro. Although many human embryos are aneuploid and genomically imbalanced, often as a result of meiotic errors inherited in the oocyte, these aneuploidies persist at the blastocyst stage and the reasons for the high incidence of developmental arrest remain unknown. Here we use genome-wide SNP genotyping and meiomapping of both polar bodies to identify maternal meiotic errors and karyomapping to fingerprint the parental chromosomes in single cells from disaggregated arrested embryos and excluded cells from blastocysts. Combined with time lapse imaging of development in culture, we demonstrate that tripolar mitoses in early cleavage cause chromosome dispersal to clones of cells with identical or closely related sub-diploid chromosome profiles resulting in intercellular partitioning of the genome. We hypothesise that following zygotic genome activation (ZGA), the combination of genomic imbalance and partial genome loss disrupts the normal pattern of embryonic gene expression blocking development at the morula-blastocyst transition. Failure to coordinate the cell cycle in early cleavage and regulate centrosome duplication is therefore a major cause of human preimplantation developmental arrest in vitro.

Preimplantation Genetic Diagnosis: The Situation in France and in Other European Countries.

Science.gov (United States)

Duguet, Anne-Marie; Boyer-Beviere, Bénédicte

2017-04-01

Preimplantation genetic diagnosis (PGD) relates exclusively to in vitro fertilisation techniques (IVF) that aim to prevent transmission of a serious genetic abnormality to the child. The genetic characteristics of the embryo created through IVF are analysed, and only the embryos free of the genetic abnormality are implanted in the womb. Performed worldwide since 1990, this technique has raised many legal and ethical debates due to the very wide variations of lawgiving between countries. This is shown by the report of the UNESCO IBC (2003), which described the techniques and the issues raised by preimplantation genetic diagnosis. In this article, the authors present the differences between prenatal diagnosis and preimplantation genetic diagnosis, the French legislation, then the range of legislation in Europe and finally the position of the European Court of Human Rights which sanctioned Italy and Latvia for refusing access to PGD.

Technical Update: Preimplantation Genetic Diagnosis and Screening.

Science.gov (United States)

Dahdouh, Elias M; Balayla, Jacques; Audibert, François; Wilson, R Douglas; Audibert, François; Brock, Jo-Ann; Campagnolo, Carla; Carroll, June; Chong, Karen; Gagnon, Alain; Johnson, Jo-Ann; MacDonald, William; Okun, Nanette; Pastuck, Melanie; Vallée-Pouliot, Karine

2015-05-01

To update and review the techniques and indications of preimplantation genetic diagnosis (PGD) and preimplantation genetic screening (PGS). Discussion about the genetic and technical aspects of preimplantation reproductive techniques, particularly those using new cytogenetic technologies and embryo-stage biopsy. Clinical outcomes of reproductive techniques following the use of PGD and PGS are included. This update does not discuss in detail the adverse outcomes that have been recorded in association with assisted reproductive technologies. Published literature was retrieved through searches of The Cochrane Library and Medline in April 2014 using appropriate controlled vocabulary (aneuploidy, blastocyst/physiology, genetic diseases, preimplantation diagnosis/methods, fertilization in vitro) and key words (e.g., preimplantation genetic diagnosis, preimplantation genetic screening, comprehensive chromosome screening, aCGH, SNP microarray, qPCR, and embryo selection). Results were restricted to systematic reviews, randomized controlled trials/controlled clinical trials, and observational studies published from 1990 to April 2014. There were no language restrictions. Searches were updated on a regular basis and incorporated in the update to January 2015. Additional publications were identified from the bibliographies of retrieved articles. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. (Table 1) BENEFITS, HARMS, AND COSTS: This update will educate readers about new preimplantation genetic concepts, directions, and technologies. The major harms and costs identified are those of assisted reproductive

Characterization of bovine embryos cultured under conditions appropriate for sustaining human naïve pluripotency

NARCIS (Netherlands)

Brinkhof, Bas; van Tol, Helena T A; Groot Koerkamp, Marian J A; Wubbolts, Richard W; Haagsman, Henk P; Roelen, Bernard A J

2017-01-01

In mammalian preimplantation development, pluripotent cells are set aside from cells that contribute to extra-embryonic tissues. Although the pluripotent cell population of mouse and human embryos can be cultured as embryonic stem cells, little is known about the pathways involved in formation of a

Effects of heat stress on bovine preimplantation embryos produced in vitro.

Science.gov (United States)

Sakatani, Miki

2017-08-19

Summer heat stress decreases the pregnancy rate in cattle and has been thought to be associated with the early embryonic death caused by the elevation of maternal body temperature. In vitro cultures have been widely used for the evaluation of effects of heat stress on oocytes, fertilization, preimplantation, and embryonic development. Susceptibility to heat stress is present in developmental stages from oocytes to cleavage-stage (before embryonic gene activation, EGA) embryos, leading to a consequent decrease in developmental competence. On the other hand, advanced-stage embryos such as morula or blastocysts have acquired thermotolerance. The mechanism for the developmental stage-dependent change in thermotolerance is considered to be the accumulation of antioxidants in embryos in response to heat-inducible production of reactive oxygen species. The supplementation of antioxidants to the culture media has been known to neutralize the detrimental effects of heat stress. Besides, EGA could be involved in acquisition of thermotolerance in later stages of embryos. Morulae or blastocysts can repair heat-induced unfolded proteins or prevent DNA damage occurring in processes such as apoptosis. Therefore, embryo transfer (ET) that can bypass the heat-sensitive stage could be a good solution to improve the pregnancy rate under heat stress. However, frozen-thawed ET could not improve the pregnancy rate as expected. Frozen-thawed blastocysts were more sensitive to heat stress and showed less proliferation upon heat exposure, compared to fresh blastocysts. Therefore, further research is required to improve the reduction in pregnancy rates due to summer heat stress.

Effect of oxygen concentration on human embryo development evaluated by time-lapse monitoring

DEFF Research Database (Denmark)

Ingerslev, Hans Jakob; Hindkjær, Johnny Juhl; Kirkegaard, Kirstine

2012-01-01

recently demonstrated to occur from first cleavage cycle in mice using time-lapse microscopy, with the largest impact on the pre-compaction stages. However, embryonic development in mice differs in many aspects from human embryonic development. The objective of this retrospective, descriptive study...... was to evaluate the influence of oxygen tension on human pre-implantation development using time-lapse monitoring. Materials and methods: Human embryos were cultured to the blastocyst stage in a time-lapse incubator (EmbryoScope™) in 20% O2 (group 1), 20% O2 for 24 hours followed by culture in 5% O2 (group 2......) or in 5% O2 (group 3). Eligible were patients with age 8 oocytes retrieved. Group 1 consisted of 120 IVF/ICSI embryos from 26 patients recruited to a study conducted to evaluate the safety of the time-lapse incubator by randomising 1:1 embryos from a patient to culture...

Endometrial signals improve embryo outcome: functional role of vascular endothelial growth factor isoforms on embryo development and implantation in mice.

Science.gov (United States)

Binder, N K; Evans, J; Gardner, D K; Salamonsen, L A; Hannan, N J

2014-10-10

Does vascular endothelial growth factor (VEGF) have important roles during early embryo development and implantation? VEGF plays key roles during mouse preimplantation embryo development, with beneficial effects on time to cavitation, blastocyst cell number and outgrowth, as well as implantation rate and fetal limb development. Embryo implantation requires synchronized dialog between maternal cells and those of the conceptus. Following ovulation, secretions from endometrial glands increase and accumulate in the uterine lumen. These secretions contain important mediators that support the conceptus during the peri-implantation phase. Previously, we demonstrated a significant reduction of VEGFA in the uterine cavity of women with unexplained infertility. Functional studies demonstrated that VEGF significantly enhanced endometrial epithelial cell adhesive properties and embryo outgrowth. Human endometrial lavages (n = 6) were obtained from women of proven fertility. Four-week old Swiss mice were superovulated and mated with Swiss males to obtain embryos for treatment with VEGF in vitro. Preimplantation embryo development was assessed prior to embryo transfer (n = 19-30/treatment group/output). Recipient F1 female mice (8-12 weeks of age) were mated with vasectomized males to induce pseudopregnancy and embryos were transferred. On Day 14.5 of pregnancy, uterine horns were collected for analysis of implantation rates as well as placental and fetal development (n = 14-19/treatment). Lavage fluid was assessed by western immunoblot analysis to determine the VEGF isoforms present. Mouse embryos were treated with either recombinant human (rh)VEGF, or VEGF isoforms 121 and 165. Preimplantation embryo development was quantified using time-lapse microscopy. Blastocysts were (i) stained for cell number, (ii) transferred to wells coated with fibronectin to examine trophoblast outgrowth or (iii) transferred to pseudo pregnant recipients to analyze implantation rates, placental and

Perturbation of the Developmental Potential of Preimplantation Mouse Embryos by Hydroxyurea

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Edward R. Hills

2010-04-01

Full Text Available Women are advised not to attempt pregnancy while on hydroxyurea (HU due to the teratogenic effects of this agent, based on results obtained from animal studies. Several case reports suggest that HU may have minimal or no teratogenic effects on the developing human fetus. Fourteen cases of HU therapy in pregnant patients diagnosed with acute or chronic myelogenous leukemia, primary thrombocythemia, or sickle cell disease (SCD have been reported. Three pregnancies were terminated by elective abortion; 1 woman developed eclampsia and delivered a phenotypically normal stillborn infant. All other patients delivered live, healthy infants without congenital anomalies. We contend that case studies such as these have too few patients and cannot effectively address the adverse effect of HU on preimplantation embryo or fetuses. The objective of this study was to assess the risks associated with a clinically relevant dose of HU used for the treatment of SCD, on ovulation rate and embryo development, using adult C57BL/6J female mice as a model. In Experiment 1, adult female mice were randomly assigned to a treatment or a control group (N = 20/group. Treatment consisted of oral HU (30 mg/kg for 28 days; while control mice received saline (HU vehicle. Five days to the cessation of HU dosing, all mice were subjected to folliculogenesis induction with pregnant mare serum gonadotropin (PMSG. Five mice/group were anesthetized at 48 hours post PMSG to facilitate blood collection via cardiac puncture for estradiol-17β (E2 measurement by RIA. Ovulation was induced in the remaining mice at 48 hours post PMSG with human chorionic gonadotropin (hCG and immediately caged with adult males for mating. Five plugged female mice/group were sacrificed for the determination of ovulation rate. The remaining mated mice were sacrificed about 26 hours post hCG, ovaries excised and weighed and embryos harvested and cultured in Whitten’s medium (WM supplemented with CZBt. In

A medium-chain fatty acid as an alternative energy source in mouse preimplantation development.

Science.gov (United States)

Yamada, Mitsutoshi; Takanashi, Kazumi; Hamatani, Toshio; Hirayama, Akiyoshi; Akutsu, Hidenori; Fukunaga, Tomoko; Ogawa, Seiji; Sugawara, Kana; Shinoda, Kosaku; Soga, Tomoyoshi; Umezawa, Akihiro; Kuji, Naoaki; Yoshimura, Yasunori; Tomita, Masaru

2012-01-01

To further optimize the culturing of preimplantation embryos, we undertook metabolomic analysis of relevant culture media using capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS). We detected 28 metabolites: 23 embryo-excreted metabolites including 16 amino acids and 5 media-derived metabolites (e.g., octanoate, a medium-chain fatty acid (MCFA)). Due to the lack of information on MCFAs in mammalian preimplantation development, this study examined octanoate as a potential alternative energy source for preimplantation embryo cultures. No embryos survived in culture media lacking FAs, pyruvate, and glucose, but supplementation of octanoate rescued the embryonic development. Immunoblotting showed significant expression of acyl-CoA dehydrogenase and hydroxyacyl-CoA dehydrogenase, important enzymes for ß-oxidation of MCFAs, in preimplantation embryo. Furthermore, CE-TOFMS traced [1-(13)C(8)] octanoate added to the culture media into intermediate metabolites of the TCA cycle via ß-oxidation in mitochondria. These results are the first demonstration that octanoate could provide an efficient alternative energy source throughout preimplantation development.

Effect of the microenvironment and embryo density on developmental characteristics and gene expression profile of bovine preimplantative embryos cultured in vitro.

Science.gov (United States)

Hoelker, Michael; Rings, Franka; Lund, Qamaruddin; Ghanem, Nasser; Phatsara, Chirawath; Griese, Josef; Schellander, Karl; Tesfaye, Dawit

2009-03-01

The Well of the Well (WOW) system has been developed to culture embryos in small groups or to track the development of single embryos. In the present study, we aimed to examine the effects of the microenvironment provided by the WOW system and embryo density on developmental rates, embryo quality and preimplantative gene expression profile of the resulting embryos. Embryos cultured in a group of 16 reached the blastocyst stage at a significantly lower level than zygotes cultured in a group of 50 (22.2 vs 30.3%), whereas zygotes cultured in WOW were able to compensate against low embryo densities, reaching a blastocyst rate as high as embryos cultured in a group of 50 (31.3 vs 30.3%). Moreover, embryos derived from WOW culture did not differ in terms of differential cell counts and apoptotic cell index compared with controls. The gene expression analysis revealed 62 transcripts to be upregulated and 33 transcripts to be downregulated by WOW culture. Comparing the in vivo derived blastocysts with the blastocysts derived from WOW culture, and group culture, expression of ATP5A1, PLAC8 and KRT8 was more similar to the embryos derived from WOW culture, whereas expression of S100A10 and ZP3 genes was more similar to blastocysts cultured in a group. In conclusion, microenvironment as well as embryo density significantly affected developmental rates. While subsequent blastocysts did not differ in terms of differential cell counts and apoptotic cell index, significant differences were observed in terms of the relative abundance of transcripts in the resulting embryos.

NMR studies of preimplantation embryo metabolism in human assisted reproductive techniques: a new biomarker for assessment of embryo implantation potential.

Science.gov (United States)

Pudakalakatti, Shivanand M; Uppangala, Shubhashree; D'Souza, Fiona; Kalthur, Guruprasad; Kumar, Pratap; Adiga, Satish Kumar; Atreya, Hanudatta S

2013-01-01

There has been growing interest in understanding energy metabolism in human embryos generated using assisted reproductive techniques (ART) for improving the overall success rate of the method. Using NMR spectroscopy as a noninvasive tool, we studied human embryo metabolism to identify specific biomarkers to assess the quality of embryos for their implantation potential. The study was based on estimation of pyruvate, lactate and alanine levels in the growth medium, ISM1, used in the culture of embryos. An NMR study involving 127 embryos from 48 couples revealed that embryos transferred on Day 3 (after 72 h in vitro culture) with successful implantation (pregnancy) exhibited significantly (p < 10(-5) ) lower pyruvate/alanine ratios compared to those that failed to implant. Lactate levels in media were similar for all embryos. This implies that in addition to lactate production, successfully implanted embryos use pyruvate to produce alanine and other cellular functions. While pyruvate and alanine individually have been used as biomarkers, the present study highlights the potential of combining them to provide a single parameter that correlates strongly with implantation potential. Copyright © 2012 John Wiley & Sons, Ltd.

A role for Aurora C in the chromosomal passenger complex during human preimplantation embryo development

NARCIS (Netherlands)

Santos, Margarida Avo; van de Werken, Christine; de Vries, Marieke; Jahr, Holger; Vromans, Martijn J. M.; Laven, Joop S. E.; Fauser, Bart C.; Kops, Geert J.; Lens, Susanne M.; Baart, Esther B.

BACKGROUND: Human embryos generated by IVF demonstrate a high incidence of chromosomal segregation errors during the cleavage divisions. To analyse underlying molecular mechanisms, we investigated the behaviour of the chromosomal passenger complex (CPC) in human oocytes and embryos. This important

Effects of sphingosine-1-phosphate on gene expression of two cell mouse embryos induced by C2-Ceramide

Directory of Open Access Journals (Sweden)

Xujing Geng

2014-06-01

Conclusions: This study provides a map of genes in the pre-implantation two cell mouse embryo. Further investigation based on these data will provide a better understanding of the effects of S1P on the pre-implantation embryos in other mammalian species, especially human.

Laboratory techniques for human embryos.

Science.gov (United States)

Geber, Selmo; Sales, Liana; Sampaio, Marcos A C

2002-01-01

This review is concerned with laboratory techniques needed for assisted conception, particularly the handling of gametes and embryos. Such methods are being increasingly refined. Successive stages of fertilization and embryogenesis require especial care, and often involve the use of micromanipulative methods for intracytoplasmic sperm injection (ICSI) or preimplantation genetic diagnosis. Embryologists must take responsibility for gamete collection and preparation, and for deciding on the means of insemination or ICSI. Embryos must be assessed in culture, during the 1-cell, cleaving and morula/blastocyst stages, and classified according to quality. Co-culture methods may be necessary. The best embryos for transfer must be selected and loaded into the transfer catheter. Embryos not transferred must be cryopreserved, which demands the correct application of current methods of media preparation, seeding and the correct speed for cooling and warming. Before too long, methods of detecting abnormal embryos and avoiding their transfer may become widespread.

Effect of oxygen concentration on human embryo development evaluated by time-lapse monitoring

DEFF Research Database (Denmark)

Ingerslev, Hans Jakob; Hindkjær, Johnny Juhl; Kirkegaard, Kirstine

2012-01-01

-points for each cell division and blastocyst stages were registered until 120 hours after oocyte retrieval. Only 2PN embryos completing the first cleavage were evaluated. The groups were compared using one-way ANOVA or Kruskall-Wallis test. Estimates are reported as medians with 95% confidence intervals. Time......Introduction: Data from a number of studies indicate -but not unequivocally- that culture of embryos in 5% O2 compared to 20% O2 improves blastocyst formation in humans and various animal species and may yield better pregnancy rates in IVF. The detrimental effects of atmospheric oxygen were...... was to evaluate the influence of oxygen tension on human pre-implantation development using time-lapse monitoring. Materials and methods: Human embryos were cultured to the blastocyst stage in a time-lapse incubator (EmbryoScope™) in 20% O2 (group 1), 20% O2 for 24 hours followed by culture in 5% O2 (group 2...

Sexing bovine pre-implantation embryos using the polymerase ...

African Journals Online (AJOL)

The paper aims to present a bovine model for human embryo sexing. Cows were super-ovulated, artificially inseminated and embryos were recovered 7 days later. Embryo biopsy was performed; DNA was extracted from blastomeres and amplified using bovine-specific and bovine-Y-chromosomespecific primers, followed ...

The status of preimplantation genetic diagnosis in Japan: a criticism.

Science.gov (United States)

Munné, Santiago; Cohen, Jacques

2004-09-01

Advances in preimplantation genetic diagnosis (PGD) are occurring worldwide. New clinics specializing in this approach to the control of disease genes or imbalanced chromosome numbers in human preimplantation embryos continue to increase. One exception is Japan, where the Japanese Society of Obstetrics and Gynecology disapproves of this practice because it discriminates against people with genetic abnormalities. Yet, some doctors there wish to introduce this method to help their couples to improved forms of IVF. This paper stresses the rights of patients to have a healthy baby, if necessary by the use of PGD. It argues against prohibition, since it complements the current nature of prenatal diagnosis and avoids the need for abortions in case of afflicted embryos. Consideration is also given to other attempts at restriction that have failed.

A methodological overview on molecular preimplantation genetic diagnosis and screening: a genomic future?

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Vendrell, Xavier; Bautista-Llácer, Rosa

2012-12-01

The genetic diagnosis and screening of preimplantation embryos generated by assisted reproduction technology has been consolidated in the prenatal care framework. The rapid evolution of DNA technologies is tending to molecular approaches. Our intention is to present a detailed methodological view, showing different diagnostic strategies based on molecular techniques that are currently applied in preimplantation genetic diagnosis. The amount of DNA from one single, or a few cells, obtained by embryo biopsy is a limiting factor for the molecular analysis. In this sense, genetic laboratories have developed molecular protocols considering this restrictive condition. Nevertheless, the development of whole-genome amplification methods has allowed preimplantation genetic diagnosis for two or more indications simultaneously, like the selection of histocompatible embryos plus detection of monogenic diseases or aneuploidies. Moreover, molecular techniques have permitted preimplantation genetic screening to progress, by implementing microarray-based comparative genome hybridization. Finally, a future view of the embryo-genetics field based on molecular advances is proposed. The normalization, cost-effectiveness analysis, and new technological tools are the next topics for preimplantation genetic diagnosis and screening. Concomitantly, these additions to assisted reproduction technologies could have a positive effect on the schedules of preimplantation studies.

Time to take human embryo culture seriously.

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Sunde, Arne; Brison, Daniel; Dumoulin, John; Harper, Joyce; Lundin, Kersti; Magli, M Cristina; Van den Abbeel, Etienne; Veiga, Anna

2016-10-01

Is it important that end-users know the composition of human embryo culture media? We argue that there is as strong case for full transparency concerning the composition of embryo culture media intended for human use. Published data suggest that the composition of embryo culture media may influence the phenotype of the offspring. A review of the literature was carried out. Data concerning the potential effects on embryo development of culture media were assessed and recommendations for users made. The safety of ART procedures, especially with respect to the health of the offspring, is of major importance. There are reports from the literature indicating a possible effect of culture conditions, including culture media, on embryo and fetal development. Since the introduction of commercially available culture media, there has been a rapid development of different formulations, often not fully documented, disclosed or justified. There is now evidence that the environment the early embryo is exposed to can cause reprogramming of embryonic growth leading to alterations in fetal growth trajectory, birthweight, childhood growth and long-term disease including Type II diabetes and cardiovascular problems. The mechanism for this is likely to be epigenetic changes during the preimplantation period of development. In the present paper the ESHRE working group on culture media summarizes the present knowledge of potential effects on embryo development related to culture media, and makes recommendations. There is still a need for large prospective randomized trials to further elucidate the link between the composition of embryo culture media used and the phenotype of the offspring. We do not presently know if the phenotypic changes induced by in vitro embryo culture represent a problem for long-term health of the offspring. Published data indicate that there is a strong case for demanding full transparency concerning the compositions of and the scientific rationale behind the

Effect of Intracytoplasmic Sperm Injection (ICSI on Mouse Embryos Preimplantational Development

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Claudia Cârstea

2012-05-01

Full Text Available It is known that the in vitro culture (IVC of preimplantation embryos is associated with changes in gene expression. It is however, not known if the method of fertilization affects the global pattern of gene expression. We compared the development of mouse blastocysts produced by intracytoplasmic sperm injection (ICSI versus blastocysts fertilized in vivo and cultured in vitro from the zygote stage (IVC. At the end of cultivation (96 hrs for blastocyst stage embryos, expanded blastocysts of each group were randomly selected, and ICM and total cells number were differentially stained. The total cell number of blastocysts was estimated by counting the total number of nuclei using DAPI staining. Cell number for inner cell mass (ICM was estimated by counting the OCT4 (POU5FL positive cells. Digitally recombined, composite images were analyzed using the Zeiss Axion Vision software and Zeiss Apotome. All 5–10 optical sections were divided using a standard grid over each layer to count all. Comparing the total cells and the ICM cells number, it appears that each method of fertilization has a unique pattern development. The developmental rate and the total cell number of the blastocyst were significantly lower in ICSI versus in vivo fertilized embryos which affect the embryonic developmental rate and the total cell number of blastocysts.

In vitro development rate of preimplantation rabbit embryos cultured with different levels of melatonin.

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Mehaisen, Gamal Mohamed Kamel; Saeed, Ayman Moustafa

2015-02-01

This study aimed to investigate the effect of melatonin supplementation at different levels in culture medium on embryo development in rabbits. Embryos of 2-4 cells, 8-16 cells and morula stages were recovered from nulliparous Red Baladi rabbit does by laparotomy technique 24, 48 and 72 h post-insemination, respectively. Normal embryos from each stage were cultured to hatched blastocyst stages in either control culture medium (TCM-199 + 20% fetal bovine serum) or control supplemented with melatonin at 10(-3) M, 10(-6) M or 10(-9) M. No effect of melatonin was found on development of embryos recovered at 24 h post-insemination. The high level of melatonin at 10(-3) M adversely affected the in vitro development rates of embryos recovered at 48 h post-insemination (52 versus 86, 87 and 80% blastocyst rate; 28 versus 66, 78 and 59% hatchability rate for 10(-3) M versus 10(-9) M, 10(-6) M and control, respectively, P< 0.05). At the morula stage, melatonin at 10-3 M significantly increased the in vitro development of embryos (92% for 10(-3) M versus 76% for control, P < 0.05), while the hatchability rate of these embryos was not improved by melatonin (16-30% versus 52% for melatonin groups versus control, P < 0.05). Results show that a moderate level of melatonin (10(-6) M) may improve the development and hatchability rates of preimplantation rabbit embryos. The addition of melatonin at a 10-3 M concentration enhances the development of rabbit morulae but may negatively affect the development of earlier embryos. More studies are needed to optimize the use of melatonin in in vitro embryo culture in rabbits.

Preimplantation genetic diagnosis associated to Duchenne muscular dystrophy.

Science.gov (United States)

Bianco, Bianca; Christofolini, Denise Maria; Conceição, Gabriel Seixas; Barbosa, Caio Parente

2017-01-01

Duchenne muscular dystrophy is the most common muscle disease found in male children. Currently, there is no effective therapy available for Duchenne muscular dystrophy patients. Therefore, it is essential to make a prenatal diagnosis and provide genetic counseling to reduce the birth of such boys. We report a case of preimplantation genetic diagnosis associated with Duchenne muscular dystrophy. The couple E.P.R., 38-year-old, symptomatic patient heterozygous for a 2 to 47 exon deletion mutation in DMD gene and G.T.S., 39-year-old, sought genetic counseling about preimplantation genetic diagnosis process. They have had a 6-year-old son who died due to Duchenne muscular dystrophy complications. The couple underwent four cycles of intracytoplasmic sperm injection (ICSI) and eight embryos biopsies were analyzed by polymerase chain reaction (PCR) for specific mutation analysis, followed by microarray-based comparative genomic hybridisation (array CGH) for aneuploidy analysis. Preimplantation genetic diagnosis revealed that two embryos had inherited the maternal DMD gene mutation, one embryo had a chromosomal alteration and five embryos were normal. One blastocyst was transferred and resulted in successful pregnancy. The other embryos remain vitrified. We concluded that embryo analysis using associated techniques of PCR and array CGH seems to be safe for embryo selection in cases of X-linked disorders, such as Duchenne muscular dystrophy.

Preimplantation genetic diagnosis and screening by array comparative genomic hybridisation: experience of more than 100 cases in a single centre.

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Chow, J Fc; Yeung, W Sb; Lee, V Cy; Lau, E Yl; Ho, P C; Ng, E Hy

2017-04-01

Preimplantation genetic screening has been proposed to improve the in-vitro fertilisation outcome by screening for aneuploid embryos or blastocysts. This study aimed to report the outcome of 133 cycles of preimplantation genetic diagnosis and screening by array comparative genomic hybridisation. This study of case series was conducted in a tertiary assisted reproductive centre in Hong Kong. Patients who underwent preimplantation genetic diagnosis for chromosomal abnormalities or preimplantation genetic screening between 1 April 2012 and 30 June 2015 were included. They underwent in-vitro fertilisation and intracytoplasmic sperm injection. An embryo biopsy was performed on day-3 embryos and the blastomere was subject to array comparative genomic hybridisation. Embryos with normal copy numbers were replaced. The ongoing pregnancy rate, implantation rate, and miscarriage rate were studied. During the study period, 133 cycles of preimplantation genetic diagnosis for chromosomal abnormalities or preimplantation genetic screening were initiated in 94 patients. Overall, 112 cycles proceeded to embryo biopsy and 65 cycles had embryo transfer. The ongoing pregnancy rate per transfer cycle after preimplantation genetic screening was 50.0% and that after preimplantation genetic diagnosis was 34.9%. The implantation rates after preimplantation genetic screening and diagnosis were 45.7% and 41.1%, respectively and the miscarriage rates were 8.3% and 28.6%, respectively. There were 26 frozen-thawed embryo transfer cycles, in which vitrified and biopsied genetically transferrable embryos were replaced, resulting in an ongoing pregnancy rate of 36.4% in the screening group and 60.0% in the diagnosis group. The clinical outcomes of preimplantation genetic diagnosis and screening using comparative genomic hybridisation in our unit were comparable to those reported internationally. Genetically transferrable embryos replaced in a natural cycle may improve the ongoing pregnancy rate

Supplementation of fetal bovine serum alters histone modification H3R26me2 during preimplantation development of in vitro produced bovine embryos

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Daniel R. Arnold

2015-07-01

Full Text Available Abstract In vitro production (IVP of bovine embryos is not only of great economic importance to the cattle industry, but is also an important model for studying embryo development. The aim of this study was to evaluate the histone modification, H3R26me2 during pre-implantation development of IVP bovine embryos cultured with or without serum supplementation and how these in vitro treatments compared to in vivo embryos at the morula stage. After in vitro maturation and fertilization, bovine embryos were cultured with either 0 or 2.5% fetal bovine serum (FBS. Development was evaluated and embryos were collected and fixed at different stages during development (2-, 4-, 8-, 16-cell, morula and blastocyst. Fixed embryos were then used for immunofluorescence utilizing an antibody for H3R26me2. Images of stained embryos were analyzed as a percentage of total DNA. Embryos cultured with 2.5% FBS developed to blastocysts at a greater rate than 0%FBS groups (34.85±5.43% vs. 23.38±2.93%; P<0.05. Levels of H3R26me2 changed for both groups over development. In the 0%FBS group, the greatest amount of H3R26me2 staining was at the 4-cell (P<0.05, 16-cell (P<0.05 and morula (P<0.05 stages. In the 2.5%FBS group, only 4-cell stage embryos were significantly higher than all other stages (P<0.01. Morula stage in vivo embryos had similar levels as the 0%FBS group, and both were significantly higher than the 2.5%FBS group. These results suggest that the histone modification H3R26me2 is regulated during development of pre-implantation bovine embryos, and that culture conditions greatly alter this regulation.

Radiotoxicity and incorporation of methyl-tritiated-thymidine on preimplantation mouse embryo. In vitro fertilization and culture

International Nuclear Information System (INIS)

Kikuchi, O.K.; Ohyama, H.; Yamada, T.

1993-04-01

In the present work different concentrations of methyl- 3 H-thymidine was added to the culture medium micro drops containing the mouse zygotes at pro nuclear stage and the embryos were cultured in vitro at 37 0 C in a humidified atmosphere with 5% of CO 2 for four days up to the expanded blastocyst stage, the established end point to calculate the L D 50 lethal dose. The blastocyst formation rate decreased with increasing concentration of tritium in medium and a value of 2.4 X 10 3 Bq/ml for L D 50 was obtained. The 3 H-Td R incorporation by the embryo during the preimplantation period was low at the beginning and increased quickly during the morula and the blastocyst development. (author)

Toward an ethical eugenics: the case for mandatory preimplantation genetic selection.

Science.gov (United States)

Appel, Jacob M

2012-01-01

Preimplantation genetic diagnosis offers the possibility of screening and terminating embryos with severe and life-threatening disabilities. This article argues that under certain conditions, the use of this technology is not merely desirable as a means to reduce human suffering but also an ethically required duty of a parent to a potential child.

Gestational surrogacy and the role of routine embryo screening: Current challenges and future directions for preimplantation genetic testing.

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Sills, E Scott; Anderson, Robert E; McCaffrey, Mary; Li, Xiang; Arrach, Nabil; Wood, Samuel H

2016-03-01

Preimplantation genetic screening (PGS) is a component of IVF entailing selection of an embryo for transfer on the basis of chromosomal normalcy. If PGS were integrated with single embryo transfer (SET) in a surrogacy setting, this approach could improve pregnancy rates, minimize miscarriage risk, and limit multiple gestations. Even without PGS, pregnancy rates for IVF surrogacy cases are generally satisfactory, especially when treatment utilizes embryos derived from young oocytes and transferred to a healthy surrogate. However, there could be a more general role for PGS in surrogacy, since background aneuploidy in embryos remains a major factor driving implantation failure and miscarriage for all infertility patients. At present, the proportion of IVF cases involving GS is limited, while the number of IVF patients requesting PGS appears to be increasing. In this report, the relevance of PGS for surrogacy in the rapidly changing field of assisted fertility medicine is discussed. © 2015 Wiley Periodicals, Inc.

p38 (Mapk14/11) occupies a regulatory node governing entry into primitive endoderm differentiation during preimplantation mouse embryo development

Czech Academy of Sciences Publication Activity Database

Thamodaran, V.; Bruce, Alexander

2016-01-01

Roč. 6, č. 9 (2016), č. článku 160190. ISSN 2046-2441 Grant - others:GA ČR(CZ) GA13-03295S Institutional support: RVO:60077344 Keywords : preimplantation mouse embryo * cell-fate * primitive endoderm Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.481, year: 2016 http://rsob.royalsocietypublishing.org/content/6/9/160190

New perspectives on preimplantation genetic diagnosis and preimplantation genetic screening

Directory of Open Access Journals (Sweden)

Chun-Kai Chen

2014-06-01

Full Text Available Preimplantation genetic diagnosis is a procedure that involves the removal of one or more nuclei from oocytes (a polar body or embryos (blastomeres or trophectoderm cells in order to test for problems in genome sequence or chromosomes of the embryo prior to implantation. It provides new hope of having unaffected children, as well as avoiding the necessity of terminating an affected pregnancy for genetic parents who carry an affected gene or have balanced chromosomal status. Polymerase chain reaction-based molecular techniques are the methods used to detect gene defects with a known sequence and X-linked diseases. The indication for using this approach has expanded for couples who are prevented from having babies because they carry a serious genetic disorder to couples with conditions that are not immediately life threatening, such as cancer predisposition genes and Huntington disease. In addition, fluorescent in situ hybridization (FISH has been widely applied for the detection of chromosome abnormalities. FISH allows the evaluation of many chromosomes at the same time, up to 15 chromosome pairs in a single cell. Preimplantation genetic screening, defined as a test that screens for aneuploidy, has been most commonly used in situations of advanced maternal age, a history of recurrent miscarriage, a history of repeated implantation failure, or a severe male factor. Unfortunately, randomized controlled trials have as yet shown no benefit with respect to preimplantation genetic screening using cleavage stage biopsy, which is probably attributable to the high levels of mosaicism at early cleavage stages and the limitations of FISH. Recently, two main types of array-based technology combined with whole genome amplification have been developed for use in preimplantation genetic diagnosis; these are comparative genomic hybridization and single nucleotide polymorphism-based arrays. Both allow the analysis of all chromosomes, and the latter also allows

Preferential selection and transfer of euploid noncarrier embryos in preimplantation genetic diagnosis cycles for reciprocal translocations.

Science.gov (United States)

Wang, Li; Shen, Jiandong; Cram, David S; Ma, Minyue; Wang, Hui; Zhang, Wenke; Fan, Junmei; Gao, Zhiying; Zhang, Liwen; Li, Zhifeng; Xu, Mengnan; Leigh, Don A; Trounson, Alan O; Liu, Jiayin; Yao, Yuanqing

2017-10-01

To develop and validate a new strategy to distinguish between balanced/euploid carrier and noncarrier embryos in preimplantation genetic diagnosis (PGD) cycles for reciprocal translocations and to successfully achieve a live birth after selective transfer of a noncarrier embryo. Retrospective and prospective study. In vitro fertilization (IVF) units. Eleven patients undergoing mate pair sequencing for identification of translocation breakpoints, followed by clinical PGD cycles. Embryo biopsy with 24-chromosome testing to determine carrier status of balanced/euploid embryos. Definition of translocation breakpoints and polymerase chain reaction (PCR) diagnostic primers, correct diagnosis of euploid embryos for carrier status, and a live birth with a normal karyotype after transfer of a noncarrier embryo. In 9 of 11 patients (82%), translocation breakpoints were successfully identified. In four patients with a term PGD pregnancy established with a balanced/euploid embryo of unknown carrier status, the correct carrier status was retrospectively determined, matching with the cytogenetic karyotype of the resulting newborns. In a prospective PGD cycle undertaken by a patient with a 46,XY,t(7;14)(q22;q24.3) translocation, the four balanced/euploid embryos identified comprised three carriers and one noncarrier. Transfer of the noncarrier embryo resulted in birth of a healthy girl who was subsequently confirmed with a normal 46,XX karyotype. The combination of mate pair sequencing and PCR breakpoint analysis of balanced reciprocal translocation derivatives is a novel, reliable, and accurate strategy for distinguishing between carrier and noncarrier balanced/euploid embryos. The method has potential application in clinical PGD cycles for patients with reciprocal translocations or other structural rearrangements. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Preimplantation Genetic Diagnosis for Stargardt Disease

Science.gov (United States)

Sohrab, Mahsa A.; Allikmets, Rando; Guarnaccia, Michael M.; Smith, R. Theodore

2010-01-01

Purpose To report the first use of in vitro fertilization (IVF) and preimplantation genetic diagnosis to achieve an unaffected pregnancy in an autosomal-recessive retinal dystrophy. Design Case report. Methods An affected male with Stargardt disease and his carrier wife underwent IVF. Embryos obtained by intracytoplasmic sperm injection underwent single-cell DNA testing via polymerase chain reaction and restriction enzyme analysis to detect the presence of ABCA4 mutant alleles. Embryos were diagnosed as being either affected by or carriers for Stargardt disease. A single carrier embryo was implanted. Results Chorionic villus sampling performed during the first trimester verified that the fetus possessed only one mutant paternal allele and one normal maternal allele, thus making her an unaffected carrier of the disease. A healthy, live-born female was delivered. Conclusion IVF and preimplantation genetic diagnosis can assist couples with an affected spouse and a carrier spouse with recessive retinal dystrophies to have an unaffected child. PMID:20149343

Embryo genome profiling by single-cell sequencing for preimplantation genetic diagnosis in a β-thalassemia family

DEFF Research Database (Denmark)

Xu, Yanwen; Chen, Shengpei; Yin, Xuyang

2015-01-01

for a β-thalassemia-carrier couple to have a healthy second baby. We carried out sequencing for single blastomere cells and the family trio and further developed the analysis pipeline, including recovery of the missing alleles, removal of the majority of errors, and phasing of the embryonic genome...... leukocyte antigen matching tests. CONCLUSIONS: This retrospective study in a β-thalassemia family demonstrates a method for embryo genome recovery through single-cell sequencing, which permits detection of genetic variations in preimplantation genetic diagnosis. It shows the potential of single...

Reduction of transgenerational radiation induced genetic damages observed as numerical chromosomal abnormalities in preimplantation embryos by vitamin E

International Nuclear Information System (INIS)

Salimi, M.; Mozdarani, H.

2008-01-01

To study the effects of parental gamma irradiation (4 Gy) of NMRI (Naval Medical Research Institute) mice on the numerical chromosome abnormalities in subsequent preimplantation embryos in the presence of vitamin E (200 IU/kg), super-ovulated irradiated females were mated with irradiated males at weekly intervals in successive 6 weekly periods. About 68 h post coitus, 8-cell embryos were fixed on slides using standard methods in order to screen for abnormalities in chromosome number. In embryos generated by irradiated mice, the frequency of aneuploids dramatically increased compared to control unirradiated groups (p < 0.001), while no significant difference were observed within irradiated groups mated at weekly interval. Administration of vitamin E significantly decreased chromosomal aberrations in all groups (p < 0.05). Data indicate that gamma irradiation affects spermatogenesis and oogenesis and causes DNA alterations that may lead to chromosome abnormalities in subsequent embryos. Vitamin E effectively reduced the frequency of abnormalities. The way vitamin E reduces genotoxic effects of radiation might be via radical scavenging or antioxidative mechanism. (authors)

Dynamics and ethics of comprehensive preimplantation genetic testing: a review of the challenges.

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Hens, Kristien; Dondorp, Wybo; Handyside, Alan H; Harper, Joyce; Newson, Ainsley J; Pennings, Guido; Rehmann-Sutter, Christoph; de Wert, Guido

2013-01-01

Genetic testing of preimplantation embryos has been used for preimplantation genetic diagnosis (PGD) and preimplantation genetic screening (PGS). Microarray technology is being introduced in both these contexts, and whole genome sequencing of blastomeres is also expeted to become possible soon. The amount of extra information such tests will yield may prove to be beneficial for embryo selection, will also raise various ethical issues. We present an overview of the developments and an agenda-setting exploration of the ethical issues. The paper is a joint endeavour by the presenters at an explorative 'campus meeting' organized by the European Society of Human Reproduction and Embryology in cooperation with the department of Health, Ethics & Society of the Maastricht University (The Netherlands). The increasing amount and detail of information that new screening techniques such as microarrays and whole genome sequencing offer does not automatically coincide with an increasing understanding of the prospects of an embryo. From a technical point of view, the future of comprehensive embryo testing may go together with developments in preconception carrier screening. From an ethical point of view, the increasing complexity and amount of information yielded by comprehensive testing techniques will lead to challenges to the principle of reproductive autonomy and the right of the child to an open future, and may imply a possible larger responsibility of the clinician towards the welfare of the future child. Combinations of preconception carrier testing and embryo testing may solve some of these ethical questions but could introduce others. As comprehensive testing techniques are entering the IVF clinic, there is a need for a thorough rethinking of traditional ethical paradigms regarding medically assisted reproduction.

Preimplantation genetic diagnosis guided by single-cell genomics

Science.gov (United States)

2013-01-01

Preimplantation genetic diagnosis (PGD) aims to help couples with heritable genetic disorders to avoid the birth of diseased offspring or the recurrence of loss of conception. Following in vitro fertilization, one or a few cells are biopsied from each human preimplantation embryo for genetic testing, allowing diagnosis and selection of healthy embryos for uterine transfer. Although classical methods, including single-cell PCR and fluorescent in situ hybridization, enable PGD for many genetic disorders, they have limitations. They often require family-specific designs and can be labor intensive, resulting in long waiting lists. Furthermore, certain types of genetic anomalies are not easy to diagnose using these classical approaches, and healthy offspring carrying the parental mutant allele(s) can result. Recently, state-of-the-art methods for single-cell genomics have flourished, which may overcome the limitations associated with classical PGD, and these underpin the development of generic assays for PGD that enable selection of embryos not only for the familial genetic disorder in question, but also for various other genetic aberrations and traits at once. Here, we discuss the latest single-cell genomics methodologies based on DNA microarrays, single-nucleotide polymorphism arrays or next-generation sequence analysis. We focus on their strengths, their validation status, their weaknesses and the challenges for implementing them in PGD. PMID:23998893

Obstetric and neonatal outcomes in blastocyst-stage biopsy with frozen embryo transfer and cleavage-stage biopsy with fresh embryo transfer after preimplantation genetic diagnosis/screening.

Science.gov (United States)

Jing, Shuang; Luo, Keli; He, Hui; Lu, Changfu; Zhang, Shuoping; Tan, Yueqiu; Gong, Fei; Lu, Guangxiu; Lin, Ge

2016-07-01

To study whether embryo biopsy for preimplantation genetic diagnosis/preimplantation genetic screening (PGD/PGS) can influence pregnancy complications and neonatal outcomes. Retrospective analysis. University-affiliated center. This study included data from women and their neonates born after PGD/PGS (n = 317). Questionnaires were designed to obtain information relating to pregnancy complications and neonatal outcomes. Two major strategies for PGD/PGS were evaluated. Blastocyst-stage biopsy and frozen embryo transfer (BB-FET) was carried out in 166 patients, and cleavage-stage biopsy and fresh embryo transfer (CB-ET) was carried out in 129 patients. The incidence of gestational hypertension was significantly higher in BB-FET compared with in CB-ET (9.0% vs. 2.3%, adjusted odds ratio [OR] and 95% confidence interval [CI], 4.85 [1.34, 17.56]). In twins, the birthweight (median [range], 2.70 kg [1.55-3.60 kg] vs. 2.50 kg [1.23-3.75 kg]) was higher in BB-FET than in CB-ET and the gestational age was longer in BB-FET than in CB-ET (median [range], 36.71 weeks [31.14-39.29 weeks] vs. 35.57 weeks [30.57-38.43 weeks]). There was no difference in the incidence of singleton births between the two groups except in the incidence of preterm births (28-37 weeks; 5.3% vs. 16.5% in CB-ET and BB-FET). No significant differences were detected in the incidence of perinatal deaths, birth defects, gender of neonates, and large for gestational age in both singletons and twins, although the numbers of some events were small. BB-FET is associated with a higher incidence of gestational hypertension but better neonatal outcomes compared with CB-ET, especially in twins. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

New perspectives on preimplantation genetic diagnosis and preimplantation genetic screening.

Science.gov (United States)

Chen, Chun-Kai; Yu, Hsing-Tse; Soong, Yung-Kuei; Lee, Chyi-Long

2014-06-01

Preimplantation genetic diagnosis is a procedure that involves the removal of one or more nuclei from oocytes (a polar body) or embryos (blastomeres or trophectoderm cells) in order to test for problems in genome sequence or chromosomes of the embryo prior to implantation. It provides new hope of having unaffected children, as well as avoiding the necessity of terminating an affected pregnancy for genetic parents who carry an affected gene or have balanced chromosomal status. Polymerase chain reaction-based molecular techniques are the methods used to detect gene defects with a known sequence and X-linked diseases. The indication for using this approach has expanded for couples who are prevented from having babies because they carry a serious genetic disorder to couples with conditions that are not immediately life threatening, such as cancer predisposition genes and Huntington disease. In addition, fluorescent in situ hybridization (FISH) has been widely applied for the detection of chromosome abnormalities. FISH allows the evaluation of many chromosomes at the same time, up to 15 chromosome pairs in a single cell. Preimplantation genetic screening, defined as a test that screens for aneuploidy, has been most commonly used in situations of advanced maternal age, a history of recurrent miscarriage, a history of repeated implantation failure, or a severe male factor. Unfortunately, randomized controlled trials have as yet shown no benefit with respect to preimplantation genetic screening using cleavage stage biopsy, which is probably attributable to the high levels of mosaicism at early cleavage stages and the limitations of FISH. Recently, two main types of array-based technology combined with whole genome amplification have been developed for use in preimplantation genetic diagnosis; these are comparative genomic hybridization and single nucleotide polymorphism-based arrays. Both allow the analysis of all chromosomes, and the latter also allows the haplotype of

EGF increases expression and activity of PAs in preimplantation rat embryos and their implantation rate

Directory of Open Access Journals (Sweden)

Har-Vardi Iris

2007-01-01

Full Text Available Abstract Background Embryo implantation plays a major role in embryogenesis and the outcome of pregnancy. Plasminogen activators (PAs have been implicated in mammalian fertilization, early stages of development and embryo implantation. As in-vitro developing embryos resulted in lower implantation rate than those developed in-vivo we assume that a reduced PAs activity may be involved. In the present work we studied the effect of EGF on PAs activity, quantity and embryo implantation. Methods Zygotes were flushed from rat oviducts on day one of pregnancy and grown in-vitro in R1ECM supplemented with EGF (10 ng/ml and were grown up to the blastocyst stage. The control groups were grown in the same medium without EGF. The distribution and quantity of the PAs were examined using fluorescence immunohistochemistry followed by measurement of PAs activity using the chromogenic assay. Implantation rate was studied using the embryo donation model. Results PAs distribution in the embryos was the same in EGF treated and untreated embryos. Both PAs were localized in the blastocysts' trophectoderm, supporting the assumption that PAs play a role in the implantation process in rats. EGF increased the quantity of uPA at all stages studied but the 8-cell stage as compared with controls. The tissue type PA (tPA content was unaffected except the 8-cell stage, which was increased. The activity of uPA increased gradually towards the blastocyst stage and more so due to the presence of EGF. The activity of tPA did not vary with the advancing developmental stages although it was also increased by EGF. The presence of EGF during the preimplantation development doubled the rate of implantation of the treated group as compared with controls.

Perkembangan Praimplantasi Embrio Mencit dengan Materi Genetik yang Berasal dari Parental, Maternal, dan Inti Sel Somatik (PRE-IMPLANTATION DEVELOPMENT OF MOUSE EMBRYO WITH GENETIC MATERIAL DERIVED FROM PARENTAL, MATERNAL AND SOMATIC CELL NUCLEUS

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Harry Murti

2014-05-01

Full Text Available Cloned embryo and parthenogenetic embryo are a potential source of stem cells for regenerativemedicine. Stem cells derived from those embryos are expected to overcome the ethical issues to the use offertilization embryos for therapeutic purposes. The pre-implantation development is a critical step fordeveloping embryos reach the blastocyst stage. The objectives in vivo of this research are to produce mousecloned embryo, parthenogenetic embryo, and fertilized embryo and to study stages of  in vitro pre-implantation development culture. In vivo fertilized embryos, mouse oocytes, and cumulus cells were usedin this study. Treatment was performed on female mice superovulated with PMSG and hCG injections.Two-cell stage of in vivo fertilized embryos were collected on the second day post hCG injection. Clonedembryos were produced through Somatic Cell Nuclear Transfer (SCNT, which included enucleation, nucleartransfer and artificial activation. Parthenogenetic embryos were produced with artificial activationtechnique. The result of the research indicated that SCNT application was able to produce cloned embryos which could develop to blastocyst stage (3,2%. In addition, artificial activation of oocytes could produceparthenogenetic embryos which were able to develop up to the blastocyst stage (8,6%. In conclusion,efficiency level of parthenogenetic embryos that is able to reach the blastocyst stage was higher than in thecloned embryos. Fertilized embryos shows a better development and more efficient compared to in vitrocloned embryos and parthenogenetic embryos cultures.

Experience of more than 100 preimplantation genetic diagnosis cycles for monogenetic diseases using whole genome amplification and linkage analysis in a single centre.

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Chow, Judy F C; Yeung, William S B; Lee, Vivian C Y; Lau, Estella Y L; Ho, P C; Ng, Ernest H Y

2015-08-01

To report the outcomes of more than 100 cycles of preimplantation genetic diagnosis for monogenetic diseases. Case series. Tertiary assisted reproductive centre in Hong Kong, where patients needed to pay for the cost of preimplantation genetic diagnosis on top of standard in-vitro fertilisation charges. Patients undergoing preimplantation genetic diagnosis for monogenetic diseases at the Centre of Assisted Reproduction and Embryology, Queen Mary Hospital-The University of Hong Kong between 1 August 2007 and 30 April 2014 were included. In-vitro fertilisation, intracytoplasmic sperm injection, embryo biopsy, and preimplantation genetic diagnosis. Ongoing pregnancy rate and implantation rate. Overall, 124 cycles of preimplantation genetic diagnosis were initiated in 76 patients, 101 cycles proceeded to preimplantation genetic diagnosis, and 92 cycles had embryo transfer. The ongoing pregnancy rate was 28.2% per initiated cycle and 38.0% per embryo transfer, giving an implantation rate of 35.2%. There were 16 frozen-thawed embryo transfer cycles in which, following preimplantation genetic diagnosis, cryopreserved embryos were replaced resulting in an ongoing pregnancy rate of 37.5% and implantation rate of 30.0%. The cumulative ongoing pregnancy rate was 33.1%. The most frequent indication for preimplantation genetic diagnosis was thalassaemia, followed by neurodegenerative disorder and cancer predisposition. There was no misdiagnosis. Preimplantation genetic diagnosis is a reliable method to prevent couples conceiving fetuses severely affected by known genetic disorders, with ongoing pregnancy and implantation rates similar to those for in-vitro fertilisation for routine infertility treatment.

Expression of proposed implantation marker genes CDX2 and HOXB7 in the blastocyst does not distinguish viable from non-viable human embryos

DEFF Research Database (Denmark)

Kirkegaard, Kirstine; Hindkjær, Johnny Juhl; Ingerslev, Hans Jakob

2012-01-01

expression differs between viable and non-viable embryos in both human and non-humans, suggesting transcriptome analysis of trophectoderm (TE) as a novel method of improving embryo selection. Potential candidate marker genes have been identified with array studies on animal blastocysts. The aim of this study...... was to investigate the expression of selected genes in human blastocysts in relation to the outcome of implantation. Materials and methods: Embryos from 10 oatients undergoing in vitro fertilization treatment were included in the project. A single blastocyst was chosen for biopsy on the morning of day 5 after oocyte...... of 15 key genes associated with developmental competence in animals were evaluated in high quality human embryos with monogenic or chromosomal disorders from a pre-implantation genetic disorder program. Triplicate cDNA amplifications for quantitative (q) RT-PCR were performed using pre-designed gene...

Influence of embryo culture medium (G5 and HTF) on pregnancy and perinatal outcome after IVF: a multicenter RCT

NARCIS (Netherlands)

Kleijkers, S.H.; Mantikou, E.; Slappendel, E.; Consten, D.; Echten-Arends, J. van; Wetzels, A.M.M.; Wely, M. van; Smits, L.J.; Montfoort, A.P. van; Repping, S.; Dumoulin, J.C.; Mastenbroek, S.

2016-01-01

STUDY QUESTION: Does embryo culture medium influence pregnancy and perinatal outcome in IVF? SUMMARY ANSWER: Embryo culture media used in IVF affect treatment efficacy and the birthweight of newborns. WHAT IS KNOWN ALREADY: A wide variety of culture media for human preimplantation embryos in

Influence of embryo culture medium (G5 and HTF) on pregnancy and perinatal outcome after IVF: a multicenter RCT

NARCIS (Netherlands)

Kleijkers, Sander H. M.; Mantikou, Eleni; Slappendel, Els; Consten, Dimitri; van Echten-Arends, Jannie; Wetzels, Alex M.; van Wely, Madelon; Smits, Luc J. M.; van Montfoort, Aafke P. A.; Repping, Sjoerd; Dumoulin, John C. M.; Mastenbroek, Sebastiaan

2016-01-01

Does embryo culture medium influence pregnancy and perinatal outcome in IVF? Embryo culture media used in IVF affect treatment efficacy and the birthweight of newborns. A wide variety of culture media for human preimplantation embryos in IVF/ICSI treatments currently exists. It is unknown which

Influence of embryo culture medium (G5 and HTF) on pregnancy and perinatal outcome after IVF : a multicenter RCT

NARCIS (Netherlands)

Kleijkers, Sander H. M.; Mantikou, Eleni; Slappendel, Els; Consten, Dimitri; van Echten - Arends, Jannie; Wetzels, Alex M.; van Wely, Madelon; Smits, Luc J. M.; van Montfoort, Aafke P. A.; Repping, Sjoerd; Dumoulin, John C. M.; Mastenbroek, Sebastiaan

2016-01-01

Does embryo culture medium influence pregnancy and perinatal outcome in IVF? Embryo culture media used in IVF affect treatment efficacy and the birthweight of newborns. A wide variety of culture media for human preimplantation embryos in IVF/ICSI treatments currently exists. It is unknown which

The Role of Peroxisome Proliferator-Activated Receptors in the Development and Physiology of Gametes and Preimplantation Embryos

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Jaou-Chen Huang

2008-01-01

Full Text Available In several species, a family of nuclear receptors, the peroxisome proliferator-activated receptors (PPARs composed of three isotypes, is expressed in somatic cells and germ cells of the ovary as well as the testis. Invalidation of these receptors in mice or stimulation of these receptors in vivo or in vitro showed that each receptor has physiological roles in the gamete maturation or the embryo development. In addition, synthetic PPARγ ligands are recently used to induce ovulation in women with polycystic ovary disease. These results reveal the positive actions of PPAR in reproduction. On the other hand, xenobiotics molecules (in herbicides, plasticizers, or components of personal care products, capable of activating PPAR, may disrupt normal PPAR functions in the ovary or the testis and have consequences on the quality of the gametes and the embryos. Despite the recent data obtained on the biological actions of PPARs in reproduction, relatively little is known about PPARs in gametes and embryos. This review summarizes the current knowledge on the expression and the function of PPARs as well as their partners, retinoid X receptors (RXRs, in germ cells and preimplantation embryos. The effects of natural and synthetic PPAR ligands will also be discussed from the perspectives of reproductive toxicology and assisted reproductive technology.

Inverted light-sheet microscope for imaging mouse pre-implantation development.

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Strnad, Petr; Gunther, Stefan; Reichmann, Judith; Krzic, Uros; Balazs, Balint; de Medeiros, Gustavo; Norlin, Nils; Hiiragi, Takashi; Hufnagel, Lars; Ellenberg, Jan

2016-02-01

Despite its importance for understanding human infertility and congenital diseases, early mammalian development has remained inaccessible to in toto imaging. We developed an inverted light-sheet microscope that enabled us to image mouse embryos from zygote to blastocyst, computationally track all cells and reconstruct a complete lineage tree of mouse pre-implantation development. We used this unique data set to show that the first cell fate specification occurs at the 16-cell stage.

Chromosome fragility at FRAXA in human cleavage stage embryos at risk for fragile X syndrome.

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Verdyck, Pieter; Berckmoes, Veerle; De Vos, Anick; Verpoest, Willem; Liebaers, Inge; Bonduelle, Maryse; De Rycke, Martine

2015-10-01

Fragile X syndrome (FXS), the most common inherited intellectual disability syndrome, is caused by expansion and hypermethylation of the CGG repeat in the 5' UTR of the FMR1 gene. This expanded repeat, also known as the rare fragile site FRAXA, causes X chromosome fragility in cultured cells from patients but only when induced by perturbing pyrimidine synthesis. We performed preimplantation genetic diagnosis (PGD) on 595 blastomeres biopsied from 442 cleavage stage embryos at risk for FXS using short tandem repeat (STR) markers. In six blastomeres, from five embryos an incomplete haplotype was observed with loss of all alleles telomeric to the CGG repeat. In all five embryos, the incomplete haplotype corresponded to the haplotype carrying the CGG repeat expansion. Subsequent analysis of additional blastomeres from three embryos by array comparative genomic hybridization (aCGH) confirmed the presence of a terminal deletion with a breakpoint close to the CGG repeat in two blastomeres from one embryo. A blastomere from another embryo showed the complementary duplication. We conclude that a CGG repeat expansion at FRAXA causes X chromosome fragility in early human IVF embryos at risk for FXS. © 2015 Wiley Periodicals, Inc.

Technique of the `in vitro` fertilization and the culture of mouse embryos at preimplantation; Tecnica de fertilizacao `in vitro` e cultura de embrioes de camundongo durante a pre-implantacao

Energy Technology Data Exchange (ETDEWEB)

Kikuchi, Olivia Kimiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil); Yamada, Takeshi [National Inst. of Radiological Sciences, Chiba (Japan)

1993-03-01

The mammal embryo is an intensive cellular proliferating system, very radiosensitive and therefore adequate to the study of the biological effects of ionizing radiation. The technique of the in vitro fertilization and the culture of mouse embryos at preimplantation period, modified by Yamada et al (1982) to improve the efficiency of more than 95% of blastocyst formation is described. (author) 2 refs., 7 figs.

Sexing of Mouse Preimplantation Embryos Using Polymerase Chain Reaction%运用PCR对小鼠植入前胚胎进行性别诊断

Institute of Scientific and Technical Information of China (English)

李汶; 陆长富; 卢光琇

2001-01-01

In order to determine the sex of mouse embryo, 1 or 2 blastomeres were biopsied from Kun-ming-white mouse preimplantation embryo at 4-8 cells stage. The gDNA of the single-blastomere was abstracted. According to the base sequence of 145C5, a repititive sequence of Y chromosome of mouse C57BL6, a pair of primer were asigned and synthesized. The gDNA was amplified using these primers. 108 mouse preimplantation embryos were sexed via this technique. 46 male embryos and 62 female embryos were transfered into five pseudopreganant mothers respectively. 4 male litters and 9 female litters were obtained. The diagnosis positive　rate was 100%(4/4) and 70% (9/13)respectively. The result of PCR indecated that there was no difference between the repititive sequence of Y chromosome in mouse C57BL6 and Kun-ming-white mouse. The technique developed in this study might be further used for preimplantation genetic diagnosis of single-gene defects.%根据C57BL6小鼠Y染色体重复序列145C5的碱基顺序, 设计并合成一对引物, 运用PCR扩增昆明白小鼠植入前胚胎卵裂球DNA, 以确定其性别。共对108枚活检胚胎的相应卵裂球进行了性别诊断, 获雄性胚46枚, 雌性胚62枚, 移植后分别获雄性仔鼠4只, 准确率100%(4/4), 雌性仔鼠9只, 准确率70%(9/13)。本研究结果表明小鼠Y染色体重复序列145C5的碱基顺序在C57BL6小鼠和昆明白小鼠中基本一致；为农牧业动物进行性别选择和运用PCR进行单基因病植入前遗传学诊断提供了方法学基础。

Comprehensive preimplantation genetic screening and sperm deoxyribonucleic acid fragmentation from three males carrying balanced chromosome rearrangements.

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Ramos, Laia; Daina, Gemma; Del Rey, Javier; Ribas-Maynou, Jordi; Fernández-Encinas, Alba; Martinez-Passarell, Olga; Boada, Montserrat; Benet, Jordi; Navarro, Joaquima

2015-09-01

To assess whether preimplantation genetic screening can successfully identify cytogenetically normal embryos in couples carrying balanced chromosome rearrangements in addition to increased sperm DNA fragmentation. Comprehensive preimplantation genetic screening was performed on three couples carrying chromosome rearrangements. Sperm DNA fragmentation was assessed for each patient. Academic center. One couple with the male partner carrying a chromosome 2 pericentric inversion and two couples with the male partners carrying a Robertsonian translocation (13:14 and 14:21, respectively). A single blastomere from each of the 18 cleavage-stage embryos obtained was analysed by metaphase comparative genomic hybridization. Single- and double-strand sperm DNA fragmentation was determined by the alkaline and neutral Comet assays. Single- and double-strand sperm DNA fragmentation values and incidence of chromosome imbalances in the blastomeres were analyzed. The obtained values of single-strand sperm DNA fragmentation were between 47% and 59%, and the double-strand sperm DNA fragmentation values were between 43% and 54%. No euploid embryos were observed in the couple showing the highest single-strand sperm DNA fragmentation. However, euploid embryos were observed in the other two couples: embryo transfer was performed, and pregnancy was achieved by the couple showing the lowest sperm DNA fragmentation values. Preimplantation genetic screening enables the detection of euploid embryos in couples affected by balanced chromosome rearrangements and increased sperm DNA fragmentation. Even though sperm DNA fragmentation may potentially have clinical consequences on fertility, comprehensive preimplantation genetic screening allows for the identification and transfer of euploid embryos. Copyright © 2015. Published by Elsevier Inc.

Tripolar mitosis in human cells and embryos: occurrence, pathophysiology and medical implications.

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Kalatova, Beata; Jesenska, Renata; Hlinka, Daniel; Dudas, Marek

2015-01-01

Tripolar mitosis is a specific case of cell division driven by typical molecular mechanisms of mitosis, but resulting in three daughter cells instead of the usual count of two. Other variants of multipolar mitosis show even more mitotic poles and are relatively rare. In nature, this phenomenon was frequently observed or suspected in multiple common cancers, infected cells, the placenta, and in early human embryos with impaired pregnancy-yielding potential. Artificial causes include radiation and various toxins. Here we combine several pieces of the most recent evidence for the existence of different types of multipolar mitosis in preimplantation embryos together with a detailed review of the literature. The related molecular and cellular mechanisms are discussed, including the regulation of centriole duplication, mitotic spindle biology, centromere functions, cell cycle checkpoints, mitotic autocorrection mechanisms, and the related complicating factors in healthy and affected cells, including post-mitotic cell-cell fusion often associated with multipolar cell division. Clinical relevance for oncology and embryo selection in assisted reproduction is also briefly discussed in this context. Copyright © 2014 Elsevier GmbH. All rights reserved.

In vitro culture of pre-implanted mouse embryos. A model system for studying combined effects

International Nuclear Information System (INIS)

Streffer, C.; Beuningen, D. van; Molls, M.; Pon, A.; Schulz, S.; Zamboglou, N.

1978-01-01

Studies on combined effects, e.g. interaction between chemical toxicants and ionizing radiation, are difficult to perform, as they are dependent on many factors (substance concentration, radiation dose, sequence of treatments, etc.). In order to obtain data from such studies it is necessary to establish a comparatively simple experimental model system. We have established such a model system by studying combined effects on pre-implanted mouse embryos cultured in vitro. This system has the following advantages: (1) The embryos can be cultivated for several days in vitro; (2) Their physiological intactness can be tested; and (3) Cell proliferation, cell killing and chromosomal damage can be investigated comparatively easily. The embryos are isolated at the 2-cell stage and incubated in a culture medium in vitro. The development of the embryos is followed under the microscope until the development of blastocysts or the hatching of blastocysts is observed. These blastocysts can be transplanted to fostered mice and the development of normal animals determined. The proliferation kinetics can be studied easily, and the methods are described. A method has also been developed to measure the DNA content of individual cells by microscope fluorometry. After treatment of the embryos with ionizing radiation or drugs the release of micronuclei has been observed from the cell nuclei, which is an expression for chromosomal damage. Substances or radionuclides can be added to the culture medium or external irradiation can be performed during the culture period. Also the combined effects of radiation and heating can be studied. The effects of X-rays and tritiated compounds have also been investigated. The combined effects of radiation with antibiotics such as actinomycin D, and environmental toxicants such as lead, have been determined. The system described has been useful to evaluate cytological, teratogenic and cytogenetic effects

Preimplantation genetic diagnosis for cystic fibrosis: a case report

Science.gov (United States)

Biazotti, Maria Cristina Santoro; Pinto, Walter; de Albuquerque, Maria Cecília Romano Maciel; Fujihara, Litsuko Shimabukuro; Suganuma, Cláudia Haru; Reigota, Renata Bednar; Bertuzzo, Carmen Sílvia

2015-01-01

Cystic fibrosis is an autosomal recessive disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator gene. This disorder produces a variable phenotype including lung disease, pancreatic insufficiency, and meconium ileus plus bilateral agenesis of the vas deferens causing obstructive azoospermia and male infertility. Preimplantation genetic diagnosis is an alternative that allows identification of embryos affected by this or other genetic diseases. We report a case of couple with cystic fibrosis; the woman had the I148 T mutation and the man had the Delta F508 gene mutation. The couple underwent in vitro fertilization, associated with preimplantation genetic diagnosis, and with subsequent selection of healthy embryos for uterine transfer. The result was an uneventful pregnancy and delivery of a healthy male baby. PMID:25993078

Preimplantation genetic diagnosis to improve pregnancy outcomes in subfertility.

Science.gov (United States)

Simpson, Joe Leigh

2012-12-01

Pre-implantation genetic diagnosis provides prenatal genetic diagnosis before implantation, thus allowing detection of chromosomal abnormalities and their exclusion from embryo transfer in assisted reproductive technologies. Polar body, blastomere or trophectoderm can each be used to obtain requisite genetic or embryonic DNA. Pre-implantation genetic diagnosis for excluding unbalanced translocations is well accepted, and pre-implantation genetic diagnosis aneuploidy testing to avoid repeated pregnancy losses in couples having recurrent aneuploidy is efficacious in reducing miscarriages. Controversy remains about whether pre-implantation genetic diagnosis aneuploidy testing improves take home pregnancy rates, for which reason adherence to specific indications is recommended while the issue is being adjudicated. Current recommendations are for obligatory 24 chromosome testing, most readily using array comparative genome hybridisation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Vitrified/warmed single blastocyst transfer in preimplantation genetic diagnosis/preimplantation genetic screening cycles.

Science.gov (United States)

Huang, Jin; Li, Rong; Lian, Ying; Chen, Lixue; Shi, Xiaodan; Qiao, Jie; Liu, Ping

2015-01-01

To investigate the single blastocyst transfer in preimplantation genetic diagnosis (PGD)/preimplantation genetic screening (PGS) cycles. 80 PGD/PGS cycles undergoing blastocyst biopsy were studied. There were 88 warming cycles during the study period. Only one warmed blastocyst was transferred per cycle. The outcomes were followed up to the infants were born. The embryo implantation rate was 54.55% (48/88). The clinical pregnancy rate was 54.55% (48/88) per transfer cycle and 60% (48/80) per initial PGD/PGS cycle. There was no multi-pregnant in this study. The live birth rate was 42.05% (37/88) per transfer cycle and 46.25% (37/80) per initial PGD/PGS cycle. In PGD/PGS cycles, single blastocyst transfer reduces the multiple pregnancy rate without affecting the clinical outcomes.

Risk to preimplantation mouse embryos of combinations of heavy metals and radiation

International Nuclear Information System (INIS)

Mueller, W.-U.; Streffer, C.

1987-01-01

The influence of arsenic, cadmium, lead or mercury on radiation risk to preimplantation mouse embryos in vitro was studied under various conditions. Morphological development, cell proliferation, and formation of micronuclei were used for assessment of risk after combined exposure to these metals and X-rays. No conditions were found under which arsenic altered radiation risk; the effects were merely additive. Cadmium acted similarly, though a few results indicated that morphological development might be impaired more strongly after combined exposure than expected from the addition of the single effects. Lead enhanced radiation risk with regard to micronucleus formation, but had an additive effect only in the case of morphological development and cell proliferation. Of all four metals, mercury had the greatest potential for enhancement of radiation risk, when morphological development and cell proliferation were studied. The observed combination effects exceeded even those effects which were calculated by taking into account the shape of the dose-effect curves (isobologram analysis, envelope of additivity). Mercury neither induced micro-nuclei nor enhanced their formation in combination experiments. (author)

Impact of preimplantation genetic screening on donor oocyte-recipient cycles in the United States.

Science.gov (United States)

Barad, David H; Darmon, Sarah K; Kushnir, Vitaly A; Albertini, David F; Gleicher, Norbert

2017-11-01

Our objective was to estimate the contribution of preimplantation genetic screening to in vitro fertilization pregnancy outcomes in donor oocyte-recipient cycles. This was a retrospective cross-sectional study of US national data from the Society for Assisted Reproductive Technology Clinic Outcome Reporting System between 2005 and 2013. Society for Assisted Reproductive Technology Clinic Outcome Reporting relies on voluntarily annual reports by more than 90% of US in vitro fertilization centers. We evaluated pregnancy and live birth rates in donor oocyte-recipient cycles after the first embryo transfer with day 5/6 embryos. Statistical models, adjusted for patient and donor ages, number of embryos transferred, race, infertility diagnosis, and cycle year were created to compare live birth rates in 392 preimplantation genetic screening and 20,616 control cycles. Overall, pregnancy and live birth rates were significantly lower in preimplantation genetic screening cycles than in control cycles. Adjusted odds of live birth for preimplantation genetic screening cycles were reduced by 35% (odds ratio, 0.65, 95% confidence interval, 0.53-0.80; P cycles over the past 9 years, has not been associated with improved odds of live birth or reduction in miscarriage rates. Copyright © 2017 Elsevier Inc. All rights reserved.

Successful pregnancy with preimplantation genetic diagnosis in a woman with mosaic Turner syndrome.

Science.gov (United States)

Onalan, Gogsen; Yilmaz, Zerrin; Durak, Tulay; Sahin, Feride Iffet; Zeyneloglu, Hulusi Bulent

2011-04-01

To determine the efficacy of the preimplantation cytogenetic analysis of the embryos obtained from patient with mosaic Turner syndrome before an IVF program. Prospective cytogenetic analysis. University-based tertiary medical center. A 29 year-old female, a partner in a couple with male factor infertility, was diagnosed with mosaic Turner syndrome with a 45,X [17]/46,XX [13] karyotype. Preimplantation genetic diagnosis was performed on four blastomeres obtained from four different embryos by fluorescence in situ hybridization probes specific to chromosomes X, Y, 13, 18, 21 in an intracytoplasmic sperm injection cycle. Blastomeres with normal signals. Two blastomeres detected as normal were transferred and pregnancy was achieved. Preimplantation Genetic Diagnose should be considered in the infertility treatment of the patient with mosaic Turner Syndrome. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Application of preimplantation genetic diagnosis in equine blastocysts

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Grady ST

2016-08-01

Full Text Available Pre-implantation genetic diagnosis (PGD is a procedure used to screen in vitroproduced embryos or embryos recovered after uterine flush to determine genetic traits by DNA testing prior to transfer into the uterus. Biopsy methods to obtain a sample of cells for genetic analysis before implantation have been successful in small embryos (morulae and blastocysts 300 µm diameter. The successful biopsy of expanded equine blastocysts via micromanipulation, with subsequent normal pregnancy rates, was first reported in 2010. Direct PCR may be performed when evaluating only one gene, such as for embryo sexing, while whole genome amplification is effective for subsequent multiplex PCR of multiple genes.

Human oocyte oolemma characteristic is positively related to embryo developmental competence after ICSI procedure

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Mohamed A. Danfour

2010-10-01

Conclusion: The current study provides evidence that preselection at a very early stage based on oolemma behavior may be helpful to identify a subgroup of preimplantation embryos with good prognostic to form blastocyst and consequently to implant and to give pregnancy.

DNA methylation in porcine preimplantation embryos developed in vivo and produced by in vitro fertilization, parthenogenetic activation and somatic cell nuclear transfer

DEFF Research Database (Denmark)

Deshmukh, Rahul Shahaji; Østrup, Olga; Østrup, Esben

2011-01-01

DNA demethylation and remethylation are crucial for reprogramming of the differentiated parental/somatic genome in the recipient ooplasm upon somatic cell nuclear transfer. Here, we analyzed the DNA methylation dynamics during porcine preimplantation development. Porcine in vivo developed (IV......), in vitro fertilized (IVF), somatic cell nuclear transfer (SCNT) and parthenogenetically activated (PA) embryos were evaluated for DNA methylation quantification at different developmental stages. Fertilized (IV and IVF) one-cell stages lacked a substantial active demethylation of the paternal genome...

DNA methylation in porcine preimplantation embryos developed in-vivo or produced by in-vitro fertilization, parthenogenetic activation and somatic cell nuclear transfer

DEFF Research Database (Denmark)

Deshmukh, Rahul Shahaji; Østrup, Olga; Østrup, Esben

2011-01-01

DNA demethylation and remethylation are crucial for reprogramming of the differentiated parental/somatic genome in the recipient ooplasm upon somatic cell nuclear transfer. Here, we analyzed the DNA methylation dynamics during porcine preimplantation development. Porcine in vivo developed (IV......), in vitro fertilized (IVF), somatic cell nuclear transfer (SCNT) and parthenogenetically activated (PA) embryos were evaluated for DNA methylation quantification at different developmental stages. Fertilized (IV and IVF) one-cell stages lacked a substantial active demethylation of the paternal genome...

Preimplantation diagnosis of genetic diseases

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Adiga S

2010-01-01

Full Text Available One of the landmarks in clinical genetics is prenatal diagnosis of genetic disorders. The recent advances in the field have made it possible to diagnose the genetic conditions in the embryos before implantation in a setting of in vitro fertilization. Polymerase chain reaction and fluorescence in situ hybridization are the two common techniques employed on a single or two cells obtained via embryo biopsy. The couple who seek in vitro fertilization may screen their embryos for aneuploidy and the couple at risk for a monogenic disorder but averse to abortion of the affected fetuses after prenatal diagnosis, are likely to be the best candidates to undergo this procedure. This article reviews the technique, indications, benefits, and limitations of pre-implantation genetic testing in clinical practice.

Assessment of human embryo development using morphological criteria in an era of time-lapse, algorithms and 'OMICS': is looking good still important?

Science.gov (United States)

Gardner, David K; Balaban, Basak

2016-10-01

With the worldwide move towards single embryo transfer there has been a renewed focus on the requirement for reliable means of assessing embryo viability. In an era of 'OMICS' technologies, and algorithms created through the use of time-lapse microscopy, the actual appearance of the human embryo as it progresses through each successive developmental stage to the blastocyst appears to have been somewhat neglected in recent years. Here we review the key features of the human preimplantation embryo and consider the relationship between morphological characteristics and developmental potential. Further, the impact of the culture environment on morphological traits, how key morphological qualities reflect aspects of embryo physiology, and how computer-assisted analysis of embryo morphology may facilitate a more quantitative approach to selection are discussed. The clinical introduction of time-lapse systems has reopened our eyes and given us a new vantage point from which to view the beauty of the initial stages of human life. Rather than a future in which the morphology of the embryo is deemed irrelevant, we propose that key features, such as multinucleation, cell size and blastocyst differentiation should be included in future iterations of selection/deselection algorithms. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved.For Permissions, please email: journals.permissions@oup.com.

Effects of a combination of X-rays and caffeine on preimplantation mouse embryos in vitro

International Nuclear Information System (INIS)

Mueller, W.U.; Streffer, C.; Fischer-Lahdo, C.

1983-01-01

The influence of a combination of caffeine (0.1 mM, 1 mM, or 2 mM) and X-rays (0.24 Gy, 0.94 Gy, or 1.88 Gy) on preimplantation mouse embryos in vitro was studied under different conditions. The agents were applied either singly or in combination. The embryos were irradiated in the G 2 -phase of the two-cell stage (28 h p.c. or 32 h p.c.) either 1 h after or immediately before application of caffeine. Caffeine was present during the whole incubation period (until 144 h p.c.). The effects on the microscopic visible development (formation of blastocysts 96 h p.c., hatching of blastocysts 144 h p.c.) and on the cell numbers of embryos at different times (48 h p.c., 56 h p.c., 96 h p.c., 144 h p.c.) were determined. We found conditions under which caffeine markedly enhanced radiation risk, i.e., under which the combination effect exceeded the sum of the single effects. This is true, in particular, for the embryonal development, for which the risk may almost be doubled, whereas the enhancement of risk is not so great for the proliferation of cells. In some cases the combination results lie even outside the envelope of additivity in the range of supra-additivity. The amount of caffeine necessary for such marked effects, however, is so high (at least 1 mM caffeine for rather long times), that it is almost impossible to reach them in vivo by consumption of caffeine-containing beverages. (orig.)

Embryo genome profiling by single-cell sequencing for successful preimplantation genetic diagnosis in a family harboring COL4A1 c.1537G>A; p.G513S mutation

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Nayana H Patel

2016-01-01

Full Text Available CONTEXT: Genetic profiling of embryos (also known as preimplantation genetic diagnosis before implantation has dramatically enhanced the success quotient of in vitro fertilization (IVF in recent times. The technology helps in avoiding selective pregnancy termination since the baby is likely to be free of the disease under consideration. AIM: Screening of embryos free from c.1537G>A; p.G513S mutation within the COL4A1 gene for which the father was known in before be in heterozygous condition. SUBJECTS AND METHODS: Processing of trophectoderm biopsies was done from twelve embryos for c.1537G>A; p.G513S mutation within the COL4A1 gene. DNA extracted from isolated cells were subjected to whole genome amplification using an isothermal amplification and strand displacement technology. Oligonucleotide primers bracketing the mutation were synthesized and used to amplify 162 base pairs (bp polymerase chain reaction amplicons originating from each embryo which were subsequently sequenced to detect the presence or absence of the single base polymorphism. RESULTS: Three out of 12 embryos interrogated in this study were found to be normal while 9 were found to harbor the mutation in heterozygous condition. Implantation of one of the normal embryos following by chorionic villus sampling at 11 th week of pregnancy indicated that the baby was free from c.1537G>A; p.G513S mutation within the COL4A1 gene. CONCLUSIONS: Single-cell sequencing is a helpful tool for preimplantation embryo profiling. This is the first report from India describing the birth of a normal child through IVF procedure where a potential pathogenic COL4A1 allele was avoided using this technology.

Hematopoietic Stem Cell Transplantation Using Preimplantation Genetic Diagnosis and Human Leukocyte Antigen Typing for Human Leukocyte Antigen-Matched Sibling Donor: A Turkish Multicenter Study.

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Kurekci, Emin; Küpesiz, Alphan; Anak, Sema; Öztürk, Gülyüz; Gürsel, Orhan; Aksoylar, Serap; Ileri, Talia; Kuşkonmaz, Barış; Eker, İbrahim; Cetin, Mualla; Tezcan Karasu, Gülsün; Kaya, Zühre; Fışgın, Tunç; Ertem, Mehmet; Kansoy, Savaş; Yeşilipek, Mehmet Akif

2017-05-01

Preimplantation genetic diagnosis involves the diagnosis of a genetic disorder in embryos obtained through in vitro fertilization, selection of healthy embryos, and transfer of the embryos to the mother's uterus. Preimplantation genetic diagnosis has been used not only to avoid the risk of having an affected child, but it also offers, using HLA matching, preselection of potential HLA-genoidentical healthy donor progeny for an affected sibling who requires bone marrow transplantation. Here, we share the hematopoietic stem cell transplantation results of 52 patients with different benign and malign hematological or metabolic diseases or immunodeficiencies whose donors were siblings born with this technique in Turkey since 2008. The median age of the patients' at the time of the transplantation was 8 years (range, 3 to 16 years) and the median age of the donors was 2 years (range, .5 to 6 years). The most common indication for HSCT was thalassemia major (42 of all patients, 80%). The stem cell source in all of the transplantations was bone marrow. In 37 of the transplantations, umbilical cord blood of the same donor was also used. In 50 of the 52 patients, full engraftment was achieved with a mean of 4.6 × 10 6 CD 34 + cells per kg of recipient weight. Ninety-six percent of the patients have been cured through hematopoietic stem cell transplantation without any complication. Primary engraftment failure was seen in only 2 patients with thalassemia major. All of the donors and the patients are alive with good health status. Preimplantation genetic diagnosis with HLA matching offers a life-saving chance for patients who need transplantation but lack an HLA genoidentical donor. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Male and female meiotic behaviour of an intrachromosomal insertion determined by preimplantation genetic diagnosis

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Doshi Alpesh

2010-02-01

Full Text Available Abstract Background Two related family members, a female and a male balanced carrier of an intrachromosomal insertion on chromosome 7 were referred to our centre for preimplantation genetic diagnosis. This presented a rare opportunity to investigate the behaviour of the insertion chromosome during meiosis in two related carriers. The aim of this study was to carry out a detailed genetic analysis of the preimplantation embryos that were generated from the three treatment cycles for the male and two for the female carrier. Patients underwent in vitro fertilization and on day 3, 22 embryos from the female carrier and 19 embryos from the male carrier were biopsied and cells analysed by fluorescent in situ hybridization. Follow up analysis of 29 untransferred embryos was also performed for confirmation of the diagnosis and to obtain information on meiotic and mitotic outcome. Results In this study, the female carrier produced more than twice as many chromosomally balanced embryos as the male (76.5% vs. 36%, and two pregnancies were achieved for her. Follow up analysis showed that the male carrier had produced more highly abnormal embryos than the female (25% and 15% respectively and no pregnancies occurred for the male carrier and his partner. Conclusion This study compares how an intrachromosomal insertion has behaved in the meiotic and preimplantation stages of development in sibling male and female carriers. It confirms that PGD is an appropriate treatment in such cases. Reasons for the differing outcome for the two carriers are discussed.

Culture medium, gas atmosphere and MAPK inhibition affect regulation of RNA-binding protein targets during mouse preimplantation development.

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Calder, Michele D; Watson, Patricia H; Watson, Andrew J

2011-11-01

During oogenesis, mammalian oocytes accumulate maternal mRNAs that support the embryo until embryonic genome activation. RNA-binding proteins (RBP) may regulate the stability and turnover of maternal and embryonic mRNAs. We hypothesised that varying embryo culture conditions, such as culture medium, oxygen tension and MAPK inhibition, affects regulation of RBPs and their targets during preimplantation development. STAU1, ELAVL1, KHSRP and ZFP36 proteins and mRNAs were detected throughout mouse preimplantation development, whereas Elavl2 mRNA decreased after the two-cell stage. Potential target mRNAs of RBP regulation, Gclc, Slc2a1 and Slc7a1 were detected during mouse preimplantation development. Gclc mRNA was significantly elevated in embryos cultured in Whitten's medium compared with embryos cultured in KSOMaa, and Gclc mRNA was elevated under high-oxygen conditions. Inhibition of the p38 MAPK pathway reduced Slc7a1 mRNA expression while inhibition of ERK increased Slc2a1 mRNA expression. The half-lives of the potential RBP mRNA targets are not regulated in parallel; Slc2a1 mRNA displayed the longest half-life. Our results indicate that mRNAs and proteins encoding five RBPs are present during preimplantation development and more importantly, demonstrate that expression of RBP target mRNAs are regulated by culture medium, gas atmosphere and MAPK pathways.

Oligonucleotide arrays vs. metaphase-comparative genomic hybridisation and BAC arrays for single-cell analysis: first applications to preimplantation genetic diagnosis for Robertsonian translocation carriers.

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Ramos, Laia; del Rey, Javier; Daina, Gemma; García-Aragonés, Manel; Armengol, Lluís; Fernandez-Encinas, Alba; Parriego, Mònica; Boada, Montserrat; Martinez-Passarell, Olga; Martorell, Maria Rosa; Casagran, Oriol; Benet, Jordi; Navarro, Joaquima

2014-01-01

Comprehensive chromosome analysis techniques such as metaphase-Comparative Genomic Hybridisation (CGH) and array-CGH are available for single-cell analysis. However, while metaphase-CGH and BAC array-CGH have been widely used for Preimplantation Genetic Diagnosis, oligonucleotide array-CGH has not been used in an extensive way. A comparison between oligonucleotide array-CGH and metaphase-CGH has been performed analysing 15 single fibroblasts from aneuploid cell-lines and 18 single blastomeres from human cleavage-stage embryos. Afterwards, oligonucleotide array-CGH and BAC array-CGH were also compared analysing 16 single blastomeres from human cleavage-stage embryos. All three comprehensive analysis techniques provided broadly similar cytogenetic profiles; however, non-identical profiles appeared when extensive aneuploidies were present in a cell. Both array techniques provided an optimised analysis procedure and a higher resolution than metaphase-CGH. Moreover, oligonucleotide array-CGH was able to define extra segmental imbalances in 14.7% of the blastomeres and it better determined the specific unbalanced chromosome regions due to a higher resolution of the technique (≈ 20 kb). Applicability of oligonucleotide array-CGH for Preimplantation Genetic Diagnosis has been demonstrated in two cases of Robertsonian translocation carriers 45,XY,der(13;14)(q10;q10). Transfer of euploid embryos was performed in both cases and pregnancy was achieved by one of the couples. This is the first time that an oligonucleotide array-CGH approach has been successfully applied to Preimplantation Genetic Diagnosis for balanced chromosome rearrangement carriers.

Oligonucleotide arrays vs. metaphase-comparative genomic hybridisation and BAC arrays for single-cell analysis: first applications to preimplantation genetic diagnosis for Robertsonian translocation carriers.

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Laia Ramos

Full Text Available Comprehensive chromosome analysis techniques such as metaphase-Comparative Genomic Hybridisation (CGH and array-CGH are available for single-cell analysis. However, while metaphase-CGH and BAC array-CGH have been widely used for Preimplantation Genetic Diagnosis, oligonucleotide array-CGH has not been used in an extensive way. A comparison between oligonucleotide array-CGH and metaphase-CGH has been performed analysing 15 single fibroblasts from aneuploid cell-lines and 18 single blastomeres from human cleavage-stage embryos. Afterwards, oligonucleotide array-CGH and BAC array-CGH were also compared analysing 16 single blastomeres from human cleavage-stage embryos. All three comprehensive analysis techniques provided broadly similar cytogenetic profiles; however, non-identical profiles appeared when extensive aneuploidies were present in a cell. Both array techniques provided an optimised analysis procedure and a higher resolution than metaphase-CGH. Moreover, oligonucleotide array-CGH was able to define extra segmental imbalances in 14.7% of the blastomeres and it better determined the specific unbalanced chromosome regions due to a higher resolution of the technique (≈ 20 kb. Applicability of oligonucleotide array-CGH for Preimplantation Genetic Diagnosis has been demonstrated in two cases of Robertsonian translocation carriers 45,XY,der(13;14(q10;q10. Transfer of euploid embryos was performed in both cases and pregnancy was achieved by one of the couples. This is the first time that an oligonucleotide array-CGH approach has been successfully applied to Preimplantation Genetic Diagnosis for balanced chromosome rearrangement carriers.

Oligonucleotide Arrays vs. Metaphase-Comparative Genomic Hybridisation and BAC Arrays for Single-Cell Analysis: First Applications to Preimplantation Genetic Diagnosis for Robertsonian Translocation Carriers

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Ramos, Laia; del Rey, Javier; Daina, Gemma; García-Aragonés, Manel; Armengol, Lluís; Fernandez-Encinas, Alba; Parriego, Mònica; Boada, Montserrat; Martinez-Passarell, Olga; Martorell, Maria Rosa; Casagran, Oriol; Benet, Jordi; Navarro, Joaquima

2014-01-01

Comprehensive chromosome analysis techniques such as metaphase-Comparative Genomic Hybridisation (CGH) and array-CGH are available for single-cell analysis. However, while metaphase-CGH and BAC array-CGH have been widely used for Preimplantation Genetic Diagnosis, oligonucleotide array-CGH has not been used in an extensive way. A comparison between oligonucleotide array-CGH and metaphase-CGH has been performed analysing 15 single fibroblasts from aneuploid cell-lines and 18 single blastomeres from human cleavage-stage embryos. Afterwards, oligonucleotide array-CGH and BAC array-CGH were also compared analysing 16 single blastomeres from human cleavage-stage embryos. All three comprehensive analysis techniques provided broadly similar cytogenetic profiles; however, non-identical profiles appeared when extensive aneuploidies were present in a cell. Both array techniques provided an optimised analysis procedure and a higher resolution than metaphase-CGH. Moreover, oligonucleotide array-CGH was able to define extra segmental imbalances in 14.7% of the blastomeres and it better determined the specific unbalanced chromosome regions due to a higher resolution of the technique (≈20 kb). Applicability of oligonucleotide array-CGH for Preimplantation Genetic Diagnosis has been demonstrated in two cases of Robertsonian translocation carriers 45,XY,der(13;14)(q10;q10). Transfer of euploid embryos was performed in both cases and pregnancy was achieved by one of the couples. This is the first time that an oligonucleotide array-CGH approach has been successfully applied to Preimplantation Genetic Diagnosis for balanced chromosome rearrangement carriers. PMID:25415307

[Analysis of clinical outcomes of different embryo stage biopsy in array comparative genomic hybridization based preimplantation genetic diagnosis and screening].

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Shen, J D; Wu, W; Shu, L; Cai, L L; Xie, J Z; Ma, L; Sun, X P; Cui, Y G; Liu, J Y

2017-12-25

Objective: To evaluate the efficiency of the application of array comparative genomic hybridization (array-CGH) in preimplantation genetic diagnosis or screening (PGD/PGS), and compare the clinical outcomes of different stage embryo biopsy. Methods: The outcomes of 381 PGD/PGS cycles referred in the First Affiliated Hospital of Nanjing Medical University from July 2011 to August 2015 were retrospectively analyzed. There were 320 PGD cycles with 156 cleavage-stage-biopsy cycles and 164 trophectoderm-biopsy cycles, 61 PGS cycles with 23 cleavage-stage-biopsy cycles and 38 trophectoderm-biopsy cycles. Chromosomal analysis was performed by array-CGH technology combined with whole genome amplification. Single embryo transfer was performed in all transfer cycles. Live birth rate was calculated as the main clinical outcomes. Results: The embryo diagnosis rate of PGD/PGS by array-CGH were 96.9%-99.1%. In PGD biopsy cycles, the live birth rate per embryo transfer cycle and live birth rate per embryo biopsy cycle were 50.0%(58/116) and 37.2%(58/156) in cleavage-stage-biopsy group, 67.5%(85/126) and 51.8%(85/164) in trophectoderm-biopsy group (both P 0.05). Conclusions: High diagnosis rate and idea live birth rate are achieved in PGD/PGS cycles based on array-CGH technology. The live birth rate of trophectoderm-biopsy group is significantly higher than that of cleavage-stage-biopsy group in PGD cycles; the efficiency of trophectoderm-biopsy is better.

Preimplantation genetic diagnosis for Down syndrome pregnancy

Institute of Scientific and Technical Information of China (English)

ZHANG Yu; XU Chen-ming; ZHU Yi-min; DONG Min-yue; QIAN Yu-li; JIN Fan; HUANG He-feng

2007-01-01

Objective: To evaluate the effect of preimplantation genetic diagnosis (PGD) conducted for women who had Down syndrome pregnancy previously. Methods: Trisomy 21 was diagnosed by using fluorescence in site hybridization (FISH) before embryo transfer in two women who had Down syndrome pregnancies. Each received one or two PGD cycles respectively. Results:Case 1: one PGD cycle was conducted, two oocytes were fertilized and biopsied. One embryo is of trisomy 21 and the other of monosomy 21. No embryo was transferred. Case 2: two PGD cycles were conducted, in total, sixteen oocytes were fertilized and biopsied. Four embryos were tested to be normal, six of trisomy 21, and one of monosomy 21. Five had no signal. Four normal embryos were transferred but no pregnancy resulted. Conclusion: For couples who had pregnancies with Down syndrome previously, PGD can be considered, and has been shown to be an effective strategy.

The Past, Present, and Future of Preimplantation Genetic Testing.

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Imudia, Anthony N; Plosker, Shayne

2016-06-01

Preimplantation genetic testing (PGT) of oocytes and embryos is the earliest form of prenatal testing. PGT requires in vitro fertilization for embryo creation. In the past 25 years, the use of PGT has increased dramatically. The indications of PGT include identification of embryos harboring single-gene disorders, chromosomal structural abnormalities, chromosomal numeric abnormalities, and mitochondrial disorders; gender selection; and identifying unaffected, HLA-matched embryos to permit the creation of a savior sibling. PGT is not without risks, limitations, or ethical controversies. This review discusses the techniques and clinical applications of different forms of PGT and the debate surrounding its associated uncertainty and expanded use. Copyright © 2016 Elsevier Inc. All rights reserved.

Gonadotropin Releasing Hormone Agonists or Antagonists for Preimplantation Genetic Diagnosis (PGD)? A Prospective Randomised Trial.

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Verpoest, Willem; De Vos, Anick; De Rycke, Martine; Parikh, Shruti; Staessen, Catherine; Tournaye, Herman; De Vos, Michel; Vloeberghs, Veerle; Blockeel, Christophe

2017-11-10

The use of GnRH analogue medication is essential in reproductive medicine to avoid premature ovulation by pituitary suppression for the duration of ovarian stimulation by gonadotrophins. The type of pituitary suppression by either GnRH agonist analogues versus GnRH antagonist analogues may result in different embryological hence clinical results. Preimplantation genetic diagnosis is a subtype of IVF in which embryos are created for genetic diagnosis of hereditary disorders in order to avoid genetically affected children. Embryological quality hence ovarian stimulation in preimplantation genetic diagnosis is crucial as genetic selection will reduce the number of available embryos to a fraction of the total. The aim of this study was to assess the efficiency of GnRH antagonist versus GnRH agonist treatment for pituitary suppression in ovarian stimulation for PGD, by proxy of number and quality of embryos at cleavage stage available for biopsy. We conducted a prospective randomised controlled trial comparing pituitary suppression by GnRH antagonist versus GnRH agonist in ovarian stimulation for PGD. The primary outcome measure was the number of embryos of sufficient quality for biopsy at cleavage stage. Secondary outcome parameters were the number of blastocysts available of top quality, and clinical pregnancy rate. There was no difference in number of oocytes retrieved, embryos at cleavage stage available for biopsy or embryo quality. The clinical pregnancy rate was higher in the GnRH agonist group; however the sample size was insufficient to allow conclusions. The use of GnRH agonist versus antagonist treatment does not result in differences in a number of oocytes, embryos or embryo quality in ovarian stimulation for preimplantation genetic diagnosis. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Birth of a healthy infant after preimplantation genetic diagnosis by sequential blastomere and trophectoderm biopsy for β-thalassemia and HLA genotyping.

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Milachich, Tanya; Timeva, Tanya; Ekmekci, Cumhur; Beyazyurek, Cagri; Tac, Huseyin Avni; Shterev, Atanas; Kahraman, Semra

2013-07-01

Preimplantation genetic diagnosis (PGD) is a widely used technique for couples at genetic risk and involves the diagnosis and transfer of unaffected embryos generated through in vitro fertilization (IVF) techniques. For those couples who are at risk of transmitting a genetic disease to their offspring, preimplantation embryos can be selected according to their genetic status as well as human leukocyte antigen (HLA) compatibility with the affected child. Stem cells from the resulting baby's umbilical cord blood can be used for transplantation to the affected sibling without graft rejection. Here we report successful hematopoietic stem cell transplantation (HSCT) after the birth of a healthy infant, who was born after successful PGD testing with both cleavage stage and blastocyst stage biopsy for the purpose of diagnosis of β-thalassemia and HLA compatibility. The specific feature of this work is not only to have the first successful HSCT achieved in Bulgaria after using preimplantation HLA typing technique, it also demonstrates how to accomplish this success via cross-border collaboration of different units, which makes the application of these sophisticated methods possible in hospitals not having the necessary equipments and expertise. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Preimplantation genetic diagnosis by fluorescence in situ hybridization of reciprocal and Robertsonian translocations.

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Chen, Chun-Kai; Wu, Dennis; Yu, Hsing-Tse; Lin, Chieh-Yu; Wang, Mei-Li; Yeh, Hsin-Yi; Huang, Hong-Yuan; Wang, Hsin-Shin; Soong, Yung-Kuei; Lee, Chyi-Long

2014-03-01

The presence of reciprocal and Robertsonian chromosomal rearrangement is often related to recurrent miscarriage. Using preimplantation genetic diagnosis, the abortion rate can be decreased. Cases treated at our center were reviewed. A retrospective analysis for either Robertsonian or reciprocal translocations was performed on all completed cycles of preimplantation genetic diagnosis at our center since the first reported case in 2004 until the end of 2010. Day 3 embryo biopsies were carried out, and the biopsied cell was checked by fluorescent in situ hybridization using relevant informative probes. Embryos with a normal or balanced translocation karyotype were transferred on Day 4. Thirty-eight preimplantation genetic diagnosis cycles involving 17 couples were completed. A total of 450 (82.6%) of the total oocytes were MII oocytes, and 158 (60.0%) of the two-pronuclei embryos were biopsied. In 41.4% of the fluorescent in situ hybridization analyses, the results were either normal or balanced. Embryos were transferred back after 21 cycles. Three babies were born from Robertsonian translocation carriers and another two from reciprocal translocation carriers. The miscarriage rate was 0%. Among the reciprocal translocation group, the live delivery rate was 8.3% per ovum pick-up cycle and 18.2% per embryo transfer cycle. Among the Robertsonian translocation group, the live delivery rate was 14.3% per ovum pick-up cycle and 20.0% per embryo transfer cycle. There is a trend whereby the outcome for Robertsonian translocation group carriers is better than that for reciprocal translocation group carriers. Aneuploidy screening may possibly be added in order to improve the outcome, especially for individuals with an advanced maternal age. The emergence of an array-based technology should help improve this type of analysis. Copyright © 2014. Published by Elsevier B.V.

The Effect of Prolonged Culture of Chromosomally Abnormal Human Embryos on The Rate of Diploid Cells

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Masood Bazrgar

2016-12-01

Full Text Available Background: A decrease in aneuploidy rate following a prolonged co-culture of human blastocysts has been reported. As co-culture is not routinely used in assisted reproductive technology, the present study aimed to evaluate the effect of the prolonged single culture on the rate of diploid cells in human embryos with aneuploidies. Materials and Methods: In this cohort study, we used fluorescence in situ hybridization (FISH to reanalyze surplus blastocysts undergoing preimplantation genetic diagnosis (PGD on day 3 postfertilization. They were randomly studied on days 6 or 7 following fertilization. Results: Of the 30 analyzed blastocysts, mosaicism was observed in 26(86.6%, while 2(6.7% were diploid, and 2(6.7% were triploid. Of those with mosaicism, 23(88.5% were determined to be diploid-aneuploid and 3(11.5% were aneuploid mosaic. The total frequency of embryos with more than 50% diploid cells was 33.3% that was lower on day 7 in comparison with the related value on day 6 (P<0.05; however, there were no differences when the embryos were classified according to maternal age, blastocyst developmental stage, total cell number on day 3, and embryo quality. Conclusion: Although mosaicism is frequently observed in blastocysts, the prolonged single culture of blastocysts does not seem to increase the rate of normal cells.

Lethality of radioisotopes in early mouse embryos

International Nuclear Information System (INIS)

Macqueen, H.A.

1979-01-01

The development of pre-implantation mouse embryos was found to be prevented by exposure of the embryos to [ 35 S]methionine, but not to [ 3 H]methionine. Such embryos have also been shown to be highly sensitive to [ 3 H]thymidine. These observations are discussed with reference to the path lengths and energies of electrons emitted from the different radioisotopes. (author)

Preimplantation genetic diagnosis of X-linked diseases examined by indirect linkage analysis.

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Borgulova, I; Putzova, M; Soldatova, I; Krautova, L; Pecnova, L; Mika, J; Kren, R; Potuznikova, P; Stejskal, D

2015-01-01

Many centers of assisted reproduction in the Czech Republic offer preimplantation genetic diagnosis with fluorescent in situ hybridization (FISH) to couples requiring preimplantation genetic diagnosis (PGD) of X-linked diseases. However, this process results in discarding all male embryos and is not able to distinguish a carrier or healthy female embryo in X-linked recessive disorders. The main aim of this study was to summarize a six-year period of PGD of X-linked monogenic diseases using indirect linkage analysis. We wanted to accentuate the advantage indirect analysis of PGD using multiple displacement amplification (MDA) followed by short tandem repeat (STR) analysis. We present forty-six PGD cycles, including pre-case haplotyping (PGH) panel, for fifteen X-linked diseases. Embryo transfer was made thirty-eight times and gravidity was confirmed in thirteen female probands with a success rate of pregnancy calculated at 42 %. PGD procedure using MDA amplification followed by STR analysis provides help in identifying genetic defects within embryos prior to implantation. The reliability of the method was also supported by high pregnancy rate compared to other publications, which commonly achieved a 30-35 % success rate (Tab. 2, Fig. 1, Ref. 33).

Recent advances in preimplantation genetic diagnosis

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Kahraman S

2015-04-01

Full Text Available Semra Kahraman, Çağri Beyazyürek, Hüseyin Avni Taç, Caroline Pirkevi, Murat Cetinkaya, Neşe Gülüm IVF and Reproductive Genetics Center, Istanbul Memorial Hospital, Istanbul, Turkey Abstract: Preimplantation genetic diagnosis (PGD is an important method for the identification chromosomal abnormalities and genes responsible for genetic defects in embryos that are created through in vitro fertilization before pregnancy. As the list of conditions and indications for PGD testing is continuing to extend enormously, novel in vitro fertilization techniques and newly established genetic analysis techniques have been implemented in clinical settings in the recent years. Blastocyst-stage biopsy, vitrification techniques, time-lapse imaging, whole-genome amplification, array-based diagnostic techniques, and next-generation sequencing techniques are promising techniques for the accurate diagnosis of diverse genetic conditions and also for the selection of the best embryo that has the highest implantation capacity. The timing and technique used for biopsy, the amplification techniques, the genetic diagnosis techniques, and appropriate genetic counseling play important roles in establishing a successful PGD. In this review, those key points of PGD will be reviewed in detail. Keywords: preimplantation genetic diagnosis, array comparative genomic hybridization, single-nucleotide polymorphism arrays, next-generation sequencing, monogenic disorders, aneuploidy testing 

Effect of embryo density on in vitro developmental characteristics of bovine preimplantative embryos with respect to micro and macroenvironments.

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Hoelker, M; Rings, F; Lund, Q; Phatsara, C; Schellander, K; Tesfaye, D

2010-10-01

To overcome developmental problems as a consequence of single embryo culture, the Well of the Well (WOW) culture system has been developed. In this study, we aimed to examine the effect of embryo densities with respect to both microenvironment and macroenvironment on developmental rates and embryo quality to get a deeper insight into developmentally important mechanisms. WOW diameter and depth significantly affected developmental rates (p < 0.05). WOWs with diameter of 500 μm reached significantly higher blastocyst rates (32.5 vs 21.1% vs 20.3%) compared to embryos cultured in WOWs of 300 μm diameter or plain cultured controls. Embryos cultured in WOWs with 700 μm depth reached significant higher developmental rates compared with embryos cultured in WOWs of 300 μm depth and control embryos (30.6 vs 22.6% vs 20.3%). Correlation of the embryo per WOW volume with developmental rates was higher (r(2) = 0.92, p = 0.0004) than correlation of WOW diameter or WOW depth with developmental rates. However, the embryo per WOW volume did not affect differential cell counts. An embryo per culture dish volume of 1 : 30 μl was identified to be optimal when the embryo per WOW volume was 1 : 0.27 μl increasing developmental rates up to the level of mass embryo production. Giving the opportunity to track each embryo over the complete culture period while keeping high developmental rates with normal mitotic dynamics, the results of this work will provide benefit for the single culture of embryos in human assisted reproduction, mammalian embryos with high economic interest as well as for scientific purpose. © 2009 Blackwell Verlag GmbH.

Preimplantation genetic diagnosis with HLA matching.

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Rechitsky, Svetlana; Kuliev, Anver; Tur-Kaspa, Illan; Morris, Randy; Verlinsky, Yury

2004-08-01

Preimplantation genetic diagnosis (PGD) has recently been offered in combination with HLA typing, which allowed a successful haematopoietic reconstitution in affected siblings with Fanconi anaemia by transplantation of stem cells obtained from the HLA-matched offspring resulting from PGD. This study presents the results of the first PGD practical experience performed in a group of couples at risk for producing children with genetic disorders. These parents also requested preimplantation HLA typing for treating the affected children in the family, who required HLA-matched stem cell transplantation. Using a standard IVF procedure, oocytes or embryos were tested for causative gene mutations simultaneously with HLA alleles, selecting and transferring only those unaffected embryos, which were HLA matched to the affected siblings. The procedure was performed for patients with children affected by Fanconi anaemia (FANC) A and C, different thalassaemia mutations, Wiscott-Aldrich syndrome, X-linked adrenoleukodystrophy, X-linked hyperimmunoglobulin M syndrome and X-linked hypohidrotic ectodermal displasia with immune deficiency. Overall, 46 PGD cycles were performed for 26 couples, resulting in selection and transfer of 50 unaffected HLA-matched embryos in 33 cycles, yielding six HLA-matched clinical pregnancies and the birth of five unaffected HLA-matched children. Despite the controversy of PGD use for HLA typing, the data demonstrate the usefulness of this approach for at-risk couples, not only to avoid the birth of affected children with an inherited disease, but also for having unaffected children who may also be potential HLA-matched donors of stem cells for treatment of affected siblings.

Histone variant H3.3-mediated chromatin remodeling is essential for paternal genome activation in mouse preimplantation embryos.

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Kong, Qingran; Banaszynski, Laura A; Geng, Fuqiang; Zhang, Xiaolei; Zhang, Jiaming; Zhang, Heng; O'Neill, Claire L; Yan, Peidong; Liu, Zhonghua; Shido, Koji; Palermo, Gianpiero D; Allis, C David; Rafii, Shahin; Rosenwaks, Zev; Wen, Duancheng

2018-03-09

Derepression of chromatin-mediated transcriptional repression of paternal and maternal genomes is considered the first major step that initiates zygotic gene expression after fertilization. The histone variant H3.3 is present in both male and female gametes and is thought to be important for remodeling the paternal and maternal genomes for activation during both fertilization and embryogenesis. However, the underlying mechanisms remain poorly understood. Using our H3.3B-HA-tagged mouse model, engineered to report H3.3 expression in live animals and to distinguish different sources of H3.3 protein in embryos, we show here that sperm-derived H3.3 (sH3.3) protein is removed from the sperm genome shortly after fertilization and extruded from the zygotes via the second polar bodies (PBII) during embryogenesis. We also found that the maternal H3.3 (mH3.3) protein is incorporated into the paternal genome as early as 2 h postfertilization and is detectable in the paternal genome until the morula stage. Knockdown of maternal H3.3 resulted in compromised embryonic development both of fertilized embryos and of androgenetic haploid embryos. Furthermore, we report that mH3.3 depletion in oocytes impairs both activation of the Oct4 pluripotency marker gene and global de novo transcription from the paternal genome important for early embryonic development. Our results suggest that H3.3-mediated paternal chromatin remodeling is essential for the development of preimplantation embryos and the activation of the paternal genome during embryogenesis. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Sex and PRNP genotype determination in preimplantation caprine embryos.

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Guignot, F; Perreau, C; Cavarroc, C; Touzé, J-L; Pougnard, J-L; Dupont, F; Beckers, J-F; Rémy, B; Babilliot, J-M; Bed'Hom, B; Lamorinière, J M; Mermillod, P; Baril, G

2011-08-01

The objective of this study was to test the accuracy of genotype diagnosis after whole amplification of DNA extracted from biopsies obtained by trimming goat embryos and to evaluate the viability of biopsied embryos after vitrification/warming and transfer. Whole genome amplification (WGA) was performed using Multiple Displacement Amplification (MDA). Sex and prion protein (PRNP) genotypes were determined. Sex diagnosis was carried out by PCR amplification of ZFX/ZFY and Y chromosome-specific sequences. Prion protein genotype determination was performed on codons 142, 154, 211, 222 and 240. Embryos were collected at day 7 after oestrus and biopsied either immediately after collection (blastocysts and expanded blastocysts) or after 24 h of in vitro culture (compacted morulae). Biopsied embryos were frozen by vitrification. Vitrified whole embryos were kept as control. DNA of biopsies was extracted and amplified using MDA. Sex diagnosis was efficient for 97.4% of biopsies and PRNP genotyping was determined in 78.7% of biopsies. After embryo transfer, no significant difference was observed in kidding rate between biopsied and vitrified control embryos, whereas embryo survival rate was different between biopsied and whole vitrified embryos (p = 0.032). At birth, 100% of diagnosed sex and 98.2% of predetermined codons were correct. Offspring PRNP profiles were in agreement with parental genotype. Whole genome amplification with MDA kit coupled with sex diagnosis and PRNP genotype predetermination are very accurate techniques to genotype goat embryos before transfer. These novel results allow us to plan selection of scrapie-resistant genotypes and kid sex before transfer of cryopreserved embryo. © 2010 Blackwell Verlag GmbH.

Preimplantation Genetic Testing in the 21st Century: Uncharted Territory

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Paul R. Brezina MD, MBA

2013-01-01

Full Text Available The past hundred years have given birth to arguably the most profound changes in society, medicine, and technology the world has ever witnessed. Genetics is one such field that has enjoyed a meteoric rise during this time. Progressing from Mendelian genetics to the discovery of DNA to the ability to sequence the human genome, perhaps no other discipline holds more promise to affect future change than genetics. Technology currently exists to evaluate some of the genetic information held by developing embryos in the context of an in vitro fertilization (IVF cycle. This information is then used to determine which embryos are selected for uterine transfer. Many societies have enacted legislation to protect against possible abuses utilizing this technology. However, it is incumbent upon society to continue ensuring that preimplantation genetic diagnosis (PGD–-and genetic testing in general–-is applied in a way that utilizes its potential in a responsible manner to improve health care.

Preimplantation genetic diagnosis and screening: Current status and future challenges

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Hsin-Fu Chen

2018-02-01

Full Text Available Preimplantation genetic diagnosis (PGD is a clinically feasible technology to prevent the transmission of monogenic inherited disorders in families afflicted the diseases to the future offsprings. The major technical hurdle is it does not have a general formula for all mutations, thus different gene locus needs individualized, customized design to make the diagnosis accurate enough to be applied on PGD, in which the quantity of DNA is scarce, whereas timely result is sometimes requested if fresh embryo transfer is desired. On the other hand, preimplantation genetic screening (PGS screens embryo with aneuploidy and was also known as PGD-A (A denotes aneuploidy in order to enhance the implantation rates as well as livebirth rates. In contrasts to PGD, PGS is still under ferocious debate, especially recent reports found that euploid babies were born after transferring the aneuploid embryos diagnosed by PGS back to the womb and only very few randomized trials of PGS are available in the literature. We have been doing PGD and/or PGS for more than 10 years as one of the core PGD/PGS laboratories in Taiwan. Here we provide a concise review of PGD/PGS regarding its current status, both domestically and globally, as well as its future challenges.

Long-distance transportation of primate embryos developing in culture: a preliminary study.

Science.gov (United States)

Nichols, Stephanie; Harvey, Alexandra; Gierbolini, Lynette; Gonzalez-Martinez, Janis; Brenner, Carol; Bavister, Barry

2010-03-01

Non-human primate embryos are invaluable for conducting research relevant to human infertility and stem cells, but their availability is restricted. In this preliminary study, rhesus monkey embryos were produced by IVF at the Caribbean Primate Research Centre and shipped in tubes of gassed culture medium within a battery-powered transport incubator by overnight courier to Wayne State University in Michigan. Upon arrival, the embryos were incubated in fresh culture medium to evaluate further development. In 11 shipments comprising 98 cleavage-stage embryos developing from oocytes that were mature (MII) upon collection, 51 (52%) reached advanced preimplantation stages (morula to hatched blastocyst) during prolonged culture following transportation. However, most embryos produced from oocytes that were immature (MI) at collection arrested and only 5/51 (10%) reached advanced stages of development. This study demonstrates that non-cryopreserved primate embryos can be routinely transported between distant sites without loss of developmental ability. In this way, the processes of production and study of non-cryopreserved primate embryos need not be restricted to the same or nearby laboratories. This will expand the use of these embryos for research and facilitate generation of translationally relevant information. Published by Elsevier Ltd.

Automation and Optimization of Multipulse Laser Zona Drilling of Mouse Embryos During Embryo Biopsy.

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Wong, Christopher Yee; Mills, James K

2017-03-01

Laser zona drilling (LZD) is a required step in many embryonic surgical procedures, for example, assisted hatching and preimplantation genetic diagnosis. LZD involves the ablation of the zona pellucida (ZP) using a laser while minimizing potentially harmful thermal effects on critical internal cell structures. Develop a method for the automation and optimization of multipulse LZD, applied to cleavage-stage embryos. A two-stage optimization is used. The first stage uses computer vision algorithms to identify embryonic structures and determines the optimal ablation zone farthest away from critical structures such as blastomeres. The second stage combines a genetic algorithm with a previously reported thermal analysis of LZD to optimize the combination of laser pulse locations and pulse durations. The goal is to minimize the peak temperature experienced by the blastomeres while creating the desired opening in the ZP. A proof of concept of the proposed LZD automation and optimization method is demonstrated through experiments on mouse embryos with positive results, as adequately sized openings are created. Automation of LZD is feasible and is a viable step toward the automation of embryo biopsy procedures. LZD is a common but delicate procedure performed by human operators using subjective methods to gauge proper LZD procedure. Automation of LZD removes human error to increase the success rate of LZD. Although the proposed methods are developed for cleavage-stage embryos, the same methods may be applied to most types LZD procedures, embryos at different developmental stages, or nonembryonic cells.

Derivation of HVR1, HVR2 and HVR3 human embryonic stem cell lines from IVF embryos after preimplantation genetic diagnosis (PGD) for monogenic disorder

OpenAIRE

Abdelkrim Hmadcha; Yolanda Aguilera; Maria Dolores Lozano-Arana; Nuria Mellado; Javier Sánchez; Cristina Moya; Luis Sánchez-Palazón; Jose Palacios; Guillermo Antiñolo; Bernat Soria

2016-01-01

From 106 human blastocyts donate for research after in vitro fertilization (IVF) and preimplantation genetic diagnosis (PGD) for monogenetic disorder, 3 human embryonic stem cells (hESCs) HVR1, HVR2 and HVR3 were successfully derived. HVR1 was assumed to be genetically normal, HVR2 carrying Becker muscular dystrophy and HVR3 Hemophilia B. Despite the translocation t(9;15)(q34.3;q14) detected in HVR2, all the 3 cell lines were characterised in vitro and in vivo as normal hESCs lines and were r...

Preimplantation genetic diagnosis for a patient with multiple endocrine neoplasia type 1: case report.

Science.gov (United States)

Lima, Aline Dt; Alves, Vanessa R; Rocha, Andressa R; Martinhago, Ana C; Martinhago, Ciro; Donadio, Nilka; Dzik, Artur; Cavagna, Mario; Gebrim, Luiz H

2018-03-01

Preimplantation genetic diagnosis was carried out for embryonic analysis in a patient with multiple endocrine neoplasia type 1 (MEN1). This is a rare autosomal-dominant cancer syndrome and the patients with MEN1 are characterized by the occurrence of tumors in multiple endocrine tissues, associated with germline and somatic inactivating mutations in the MEN1 gene. This case report documents a successful preimplantation genetic diagnosis (PGD) involving a couple at-risk for MEN1 syndrome, with a birth of a healthy infant. The couple underwent a cycle of controlled ovarian stimulation and intracytoplasmic sperm injection (ICSI). Embryos were biopsied at the blastocyst stage and cryopreserved; we used PCR-based DNA analysis for PGD testing. Only one of the five embryos analyzed for MEN1 syndrome was unaffected. This embryo was thawed and transferred following endometrial preparation. After positive βHCG test; clinical pregnancy was confirmed by ultrasound, and a healthy infant was born. PGD for single gene disorders has been an emerging therapeutic tool for couples who are at risk of passing a genetic disease on to their offspring.

Developmental potential of human oocytes reconstructed by transferring somatic cell nuclei into polyspermic zygote cytoplasm

International Nuclear Information System (INIS)

Fan, Yong; Chen, Xinjie; Luo, Yumei; Chen, Xiaolin; Li, Shaoying; Huang, Yulin; Sun, Xiaofang

2009-01-01

The generation of patient-specific nuclear transfer embryonic stem cells holds huge promise in modern regenerative medicine and cell-based drug discovery. Since human in vivo matured oocytes are not readily available, human therapeutic cloning is developing slowly. Here, we investigated for the first time whether human polyspermic zygotes could support preimplantation development of cloned embryos. Our results showed that polyspermic zygotes could be used as recipients for human somatic cell nuclear transfer (SCNT). The preimplantation developmental potential of SCNT embryos from polyspermic zygotes was limited to the 8-cell stage. Since ES cell lines can be derived from single blastomeres, these results may have important significance for human ES cells derived by SCNT. In addition, confocal images demonstrated that all of the SCNT embryos that failed to cleave showed abnormal microtubule organization. The results of the present study suggest that polyspermic human zygotes could be used as a potential source of recipient cytoplasm for SCNT.

Developmental potential of human oocytes reconstructed by transferring somatic cell nuclei into polyspermic zygote cytoplasm

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Fan, Yong; Chen, Xinjie; Luo, Yumei; Chen, Xiaolin; Li, Shaoying; Huang, Yulin [Institute of Gynecology and Obstetrics, The Third Affiliated Hospital of Guangzhou Medical College, Duobao Road 63, Guangzhou, Guangdong (China); Sun, Xiaofang, E-mail: xiaofangsun@hotmail.com [Institute of Gynecology and Obstetrics, The Third Affiliated Hospital of Guangzhou Medical College, Duobao Road 63, Guangzhou, Guangdong (China)

2009-04-24

The generation of patient-specific nuclear transfer embryonic stem cells holds huge promise in modern regenerative medicine and cell-based drug discovery. Since human in vivo matured oocytes are not readily available, human therapeutic cloning is developing slowly. Here, we investigated for the first time whether human polyspermic zygotes could support preimplantation development of cloned embryos. Our results showed that polyspermic zygotes could be used as recipients for human somatic cell nuclear transfer (SCNT). The preimplantation developmental potential of SCNT embryos from polyspermic zygotes was limited to the 8-cell stage. Since ES cell lines can be derived from single blastomeres, these results may have important significance for human ES cells derived by SCNT. In addition, confocal images demonstrated that all of the SCNT embryos that failed to cleave showed abnormal microtubule organization. The results of the present study suggest that polyspermic human zygotes could be used as a potential source of recipient cytoplasm for SCNT.

Single-gene testing combined with single nucleotide polymorphism microarray preimplantation genetic diagnosis for aneuploidy: a novel approach in optimizing pregnancy outcome.

Science.gov (United States)

Brezina, Paul R; Benner, Andrew; Rechitsky, Svetlana; Kuliev, Anver; Pomerantseva, Ekaterina; Pauling, Dana; Kearns, William G

2011-04-01

To describe a method of amplifying DNA from blastocyst trophectoderm cells (two or three cells) and simultaneously performing 23-chromosome single nucleotide polymorphism microarrays and single-gene preimplantation genetic diagnosis. Case report. IVF clinic and preimplantation genetic diagnostic centers. A 36-year-old woman, gravida 2, para 1011, and her husband who both were carriers of GM(1) gangliosidosis. The couple wished to proceed with microarray analysis for aneuploidy detection coupled with DNA sequencing for GM(1) gangliosidosis. An IVF cycle was performed. Ten blastocyst-stage embryos underwent trophectoderm biopsy. Twenty-three-chromosome microarray analysis for aneuploidy and specific DNA sequencing for GM(1) gangliosidosis mutations were performed. Viable pregnancy. After testing, elective single embryo transfer was performed followed by an intrauterine pregnancy with documented fetal cardiac activity by ultrasound. Twenty-three-chromosome microarray analysis for aneuploidy detection and single-gene evaluation via specific DNA sequencing and linkage analysis are used for preimplantation diagnosis for single-gene disorders and aneuploidy. Because of the minimal amount of genetic material obtained from the day 3 to 5 embryos (up to 6 pg), these modalities have been used in isolation of each other. The use of preimplantation genetic diagnosis for aneuploidy coupled with testing for single-gene disorders via trophectoderm biopsy is a novel approach to maximize pregnancy outcomes. Although further investigation is warranted, preimplantation genetic diagnosis for aneuploidy and single-gene testing seem destined to be used increasingly to optimize ultimate pregnancy success. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Effect of Cumulus cell co-culture and Protein Supplement on Success of in vitro Fertilization and Development of Pre-implanted Embryos in mice

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Muhammad-Baqir M-R. Fakhrildin

2005-06-01

Full Text Available Successful oocyte fertilization and normal embryonic development of mice were considered the most important diagnostic criteria for the safety of materials and tools used for human in vitro fertilization and embryo transfer (IVF-ET. Therefore, we studied the influence of cumulus cells co-culture and protein supplement within culture medium on percentages of in vitro fertilization (IVF and normal development of early stages of mouse embryo later. Oocytes were collected and treated with hyaluronidase to remove cumulus cells. Oocytes were divided into four groups namely: Group-1: Oocytes incubated within modified Earl’s medium (MEM supplied with 10% inactivated bovine amniotic fluid as a protein source and cumulus cells; Group-2: Oocytes incubated with MEM supplied with cumulus cells only; Group-3: Oocytes incubated with MEM supplied with 10% inactivated bovine amniotic fluid only; and Group-4: Oocytes  incubated with MEM free of both protein source and cumulus cells. For IVF, 5-6 oocytes were incubated with active spermatozoa under paraffin oil for 18-20 hours at 37° oC in 5% CO2. Percentages of IVF and embryonic development were then recorded. Best results for IVF and normal embryonic development were achieved from oocytes of Group-1 when compared to the other groups. As compared to Group-1, the percentage of IVF for Group-2 and Group-3 were decreased insignificantly and significantly (P<0.002, respectively. Significant (P<0.01 reduction in the percentages of IVF and normal embryonic development were reported in Group-4 as compared to Group-1. Therefore, it was concluded that the presence of cumulus cells co-culture and bovine amniotic fluid as a protein source within culture medium may have an important role on the fertilizing capacity of spermatozoa and oocytes and normal development of pre-implanted mouse embryo later.

Automated microinjection of recombinant BCL-X into mouse zygotes enhances embryo development.

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Xinyu Liu

Full Text Available Progression of fertilized mammalian oocytes through cleavage, blastocyst formation and implantation depends on successful implementation of the developmental program, which becomes established during oogenesis. The identification of ooplasmic factors, which are responsible for successful embryo development, is thus crucial in designing possible molecular therapies for infertility intervention. However, systematic evaluation of molecular targets has been hampered by the lack of techniques for efficient delivery of molecules into embryos. We have developed an automated robotic microinjection system for delivering cell impermeable compounds into preimplantation embryos with a high post-injection survival rate. In this paper, we report the performance of the system on microinjection of mouse embryos. Furthermore, using this system we provide the first evidence that recombinant BCL-XL (recBCL-XL protein is effective in preventing early embryo arrest imposed by suboptimal culture environment. We demonstrate that microinjection of recBCL-XL protein into early-stage embryos repairs mitochondrial bioenergetics, prevents reactive oxygen species (ROS accumulation, and enhances preimplantation embryo development. This approach may lead to a possible treatment option for patients with repeated in vitro fertilization (IVF failure due to poor embryo quality.

Derivation of HVR1, HVR2 and HVR3 human embryonic stem cell lines from IVF embryos after preimplantation genetic diagnosis (PGD for monogenic disorder

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Abdelkrim Hmadcha

2016-05-01

Full Text Available From 106 human blastocyts donate for research after in vitro fertilization (IVF and preimplantation genetic diagnosis (PGD for monogenetic disorder, 3 human embryonic stem cells (hESCs HVR1, HVR2 and HVR3 were successfully derived. HVR1 was assumed to be genetically normal, HVR2 carrying Becker muscular dystrophy and HVR3 Hemophilia B. Despite the translocation t(9;15(q34.3;q14 detected in HVR2, all the 3 cell lines were characterised in vitro and in vivo as normal hESCs lines and were registered in the Spanish Stem Cell Bank.

Laser fusion of mouse embryonic cells and intra-embryonic fusion of blastomeres without affecting the embryo integrity.

Science.gov (United States)

Krivokharchenko, Alexander; Karmenyan, Artashes; Sarkisov, Oleg; Bader, Michael; Chiou, Arthur; Shakhbazyan, Avetik

2012-01-01

Manipulation with early mammalian embryos is the one of the most important approach to study preimplantation development. Artificial cell fusion is a research tool for various biotechnological experiments. However, the existing methods have various disadvantages, first of them impossibility to fuse selected cells within multicellular structures like mammalian preimplantation embryos. In our experiments we have successfully used high repetition rate picosecond near infrared laser beam for fusion of pairs of oocytes and oocytes with blastomeres. Fused cells looked morphologically normal and keep their ability for further divisions in vitro. We also fused two or three blastomeres inside four-cell mouse embryos. The presence of one, two or three nuclei in different blastomeres of the same early preimplantation mouse embryo was confirmed under UV-light after staining of DNA with the vital dye Hoechst-33342. The most of established embryos demonstrated high viability and developed in vitro to the blastocyst stage. We demonstrated for the first time the use of laser beam for the fusion of various embryonic cells of different size and of two or three blastomeres inside of four-cell mouse embryos without affecting the embryo's integrity and viability. These embryos with blastomeres of various ploidy maybe unique model for numerous purposes. Thus, we propose laser optical manipulation as a new tool for investigation of fundamental mechanisms of mammalian development.

Defining the genomic signature of totipotency and pluripotency during early human development.

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Amparo Galan

Full Text Available The genetic mechanisms governing human pre-implantation embryo development and the in vitro counterparts, human embryonic stem cells (hESCs, still remain incomplete. Previous global genome studies demonstrated that totipotent blastomeres from day-3 human embryos and pluripotent inner cell masses (ICMs from blastocysts, display unique and differing transcriptomes. Nevertheless, comparative gene expression analysis has revealed that no significant differences exist between hESCs derived from blastomeres versus those obtained from ICMs, suggesting that pluripotent hESCs involve a new developmental progression. To understand early human stages evolution, we developed an undifferentiation network signature (UNS and applied it to a differential gene expression profile between single blastomeres from day-3 embryos, ICMs and hESCs. This allowed us to establish a unique signature composed of highly interconnected genes characteristic of totipotency (61 genes, in vivo pluripotency (20 genes, and in vitro pluripotency (107 genes, and which are also proprietary according to functional analysis. This systems biology approach has led to an improved understanding of the molecular and signaling processes governing human pre-implantation embryo development, as well as enabling us to comprehend how hESCs might adapt to in vitro culture conditions.

Mouse Embryo Compaction.

Science.gov (United States)

White, M D; Bissiere, S; Alvarez, Y D; Plachta, N

2016-01-01

Compaction is a critical first morphological event in the preimplantation development of the mammalian embryo. Characterized by the transformation of the embryo from a loose cluster of spherical cells into a tightly packed mass, compaction is a key step in the establishment of the first tissue-like structures of the embryo. Although early investigation of the mechanisms driving compaction implicated changes in cell-cell adhesion, recent work has identified essential roles for cortical tension and a compaction-specific class of filopodia. During the transition from 8 to 16 cells, as the embryo is compacting, it must also make fundamental decisions regarding cell position, polarity, and fate. Understanding how these and other processes are integrated with compaction requires further investigation. Emerging imaging-based techniques that enable quantitative analysis from the level of cell-cell interactions down to the level of individual regulatory molecules will provide a greater understanding of how compaction shapes the early mammalian embryo. © 2016 Elsevier Inc. All rights reserved.

Barcode tagging of human oocytes and embryos to prevent mix-ups in assisted reproduction technologies.

Science.gov (United States)

Novo, Sergi; Nogués, Carme; Penon, Oriol; Barrios, Leonardo; Santaló, Josep; Gómez-Martínez, Rodrigo; Esteve, Jaume; Errachid, Abdelhamid; Plaza, José Antonio; Pérez-García, Lluïsa; Ibáñez, Elena

2014-01-01

-lapse monitoring. Injected oocytes were parthenogenetically activated using ionomycin and 6-dimethylaminopurine. Blastocyst development rates of tagged (27/58) and non-tagged embryos (24/51) were equivalent, and no significant differences in the timing of key morphokinetic parameters and the number of inner cell mass cells were detected between the two groups (tagged: 24.7 ± 2.5; non-tagged: 22.3 ± 1.9), indicating that preimplantation embryo potential and quality are not affected by the barcodes. Similarly, re-expansion rates of vitrified-warmed tagged (19/21) and non-tagged (16/19) blastocysts were similar. Global identification rates of 96.9 and 89.5% were obtained in fresh (mean barcode retention: 9.22 ± 0.13) and vitrified-warmed (mean barcode retention: 7.79 ± 0.35) tagged embryos, respectively, when simulating an automatic barcode reading process, though these rates were increased to 100% just by rotating the embryos during barcode reading. Only one of the oocytes lost one barcode during intracytoplasmic injection (100% identification rate) and all oocytes retained all the barcodes after parthenogenetic activation. Although the direct embryo tagging system developed is effective, it only allows the identification and traceability of oocytes destined for ICSI and embryos. Thus, the traceability of all reproductive samples (oocytes destined for IVF and sperm) is not yet ensured. The direct embryo tagging system developed here provides fertility clinics with a novel tool to reduce the risk of mix-ups in human ARTs. The system can also be useful in research studies that require the individual identification of oocytes or embryos and their individual tracking. This study was supported by the Sociedad Española de Fertilidad, the Spanish Ministry of Education and Science (TEC2011-29140-C03) and the Generalitat de Catalunya (2009SGR-00282 and 2009SGR-00158). The authors do not have any competing interests.

Preimplantation genetic diagnosis: International standards and the law of the republic of Serbia

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Rajić Nataša

2014-01-01

Full Text Available The process of biomedical assisted reproduction, in addition to the treatment of infertility, also can be implemented for the purpose of prevention of transmission of serious hereditary disease to offspring. This is possible thanks to the preimplantation genetic diagnosis, which involves genetic testing of a few cells of the embryo in the early stage of development before implantation in a woman's body, and its elimination in the case of determining the genetic anomaly. The process of the preimplantation genetic diagnosis faces several constitutional values and raises a series of questions. Some of them were answered by European Court of Human Rights in the case Costa and Pavan v. Italiy. The subject of the paper is the analysis of this decision, which is important from a constitutional point of view, because it establishes guidelines for the interpretation of rules of domestic law. The second task of the paper is the analysis of normative solutions of our legal system in this area, in order to test their compliance with the standards set in this Court's decision.

Is the resulting phenotype of an embryo with balanced X-autosome translocation, obtained by means of preimplantation genetic diagnosis, linked to the X inactivation pattern?

Science.gov (United States)

Ferfouri, Fatma; Bernicot, Izabel; Schneider, Anouck; Haquet, Emmanuelle; Hédon, Bernard; Anahory, Tal

2016-04-01

To examine if a balanced female embryo with X-autosome translocation could, during its subsequent development, express an abnormal phenotype. Preimplantation genetic diagnosis (PGD) analysis on two female carriers with maternal inherited X-autosome translocations. Infertility center and genetic laboratory in a public hospital. Two female patients carriers undergoing PGD for a balanced X-autosome translocations: patient 1 with 46,X,t(X;2)(q27;p15) and patient 2 with 46,X,t(X;22)(q28;q12.3). PGD for balanced X-autosome translocations. PGD outcomes, fluorescence in situ hybridization in biopsied embryos and meiotic segregation patterns analysis of embryos providing from X-autosome translocation carriers. Controlled ovarian stimulation facilitated retrieval of a correct number of oocytes. One balanced embryo per patient was transferred and one developed, but the patient miscarried after 6 weeks of amenorrhea. In X-autosome translocation carriers, balanced Y-bearing embryos are most often phenotypically normal and viable. An ambiguous phenotype exists in balanced X-bearing embryos owing to the X inactivation mechanism. In 46,XX embryos issued from an alternate segregation, der(X) may be inactivated and partially spread transcriptional silencing into a translocated autosomal segment. Thus, the structural unbalanced genotype could be turned into a viable functional balanced one. It is relevant that a discontinuous silencing is observed with a partial and unpredictable inactivation of autosomal regions. Consequently, the resulting phenotype remains a mystery and is considered to be at risk of being an abnormal phenotype in the field of PGD. It is necessary to be cautious regarding to PGD management for this type of translocation, particularly in transferred female embryos. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Detrimental effects of microgravity on mouse preimplantation development in vitro.

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Sayaka Wakayama

Full Text Available Sustaining life beyond Earth either on space stations or on other planets will require a clear understanding of how the space environment affects key phases of mammalian reproduction. However, because of the difficulty of doing such experiments in mammals, most studies of reproduction in space have been carried out with other taxa, such as sea urchins, fish, amphibians or birds. Here, we studied the possibility of mammalian fertilization and preimplantation development under microgravity (microG conditions using a three-dimensional (3D clinostat, which faithfully simulates 10(-3 G using 3D rotation. Fertilization occurred normally in vitro under microG. However, although we obtained 75 healthy offspring from microG-fertilized and -cultured embryos after transfer to recipient females, the birth rate was lower than among the 1G controls. Immunostaining demonstrated that in vitro culture under microG caused slower development and fewer trophectoderm cells than in 1G controls but did not affect polarization of the blastocyst. These results suggest for the first time that fertilization can occur normally under microG environment in a mammal, but normal preimplantation embryo development might require 1G.

Pertussis toxin-catalyzed ADP-ribosylation of a G protein in mouse oocytes, eggs, and preimplantation embryos: Developmental changes and possible functional roles

Energy Technology Data Exchange (ETDEWEB)

Jones, J.; Schultz, R.M. (Univ. of Pennsylvania, Philadelphia (USA))

1990-06-01

G proteins, which in many somatic cells serve as mediators of signal transduction, were identified in preimplantation mouse embryos by their capacity to undergo pertussis toxin-catalyzed ADP-ribosylation. Two pertussis toxin (PT) substrates with Mr = 38,000 and 39,000 (alpha 38 and alpha 39) are present in approximately equal amounts. Relative to the amount in freshly isolated germinal vesicle (GV)-intact oocytes, the amount of PT-catalyzed ADP-ribosylation of alpha 38-39 falls during oocyte maturation, rises between the one- and two-cell stages, falls by the eight-cell and morula stages, and increases again by the blastocyst stage. The decrease in PT-catalyzed ADP-ribosylation of alpha 38-39 that occurs during oocyte maturation, however, does not require germinal vesicle breakdown (GVBD), since inhibiting GVBD with 3-isobutyl-1-methyl xanthine (IBMX) does not prevent the decrease in the extent of PT-catalyzed ADP-ribosylation. A biologically active phorbol diester (12-O-tetradecanoyl phorbol 13-acetate), but not an inactive one (4 alpha-phorbol 12,13-didecanoate, 4 alpha-PDD), totally inhibits the increase in PT-catalyzed ADP-ribosylation of alpha 38-39 that occurs between the one- and two-cell stage; TPA inhibits cleavage, but not transcriptional activation, which occurs in the two-cell embryo. In contrast, cytochalasin D, genistein, or aphidicolin, each of which inhibits cleavage of one-cell embryos, or alpha-amanitin or H8, each of which inhibits transcriptional activation but not cleavage of one-cell embryos, have little or inhibitory effects on the increase in PT-catalyzed ADP-ribosylation of alpha 38-39. Results of immunoblotting experiments using an antibody that is highly specific for alpha il-3 reveal the presence of a cross-reactive species of Mr = 38,000 (alpha 38) in the GV-intact oocyte, metaphase II-arrested egg, and one-, two-cell embryos.

Assay using embryo aggregation chimeras for the detection of nonlethal changes in X-irradiated mouse preimplantation embryos

International Nuclear Information System (INIS)

Obasaju, M.F.; Wiley, L.M.; Oudiz, D.J.; Miller, L.; Samuels, S.J.; Chang, R.J.; Overstreet, J.W.

1988-01-01

We have developed a short-term in vitro assay for the detection of sublethal effects produced by very low levels of ionizing radiation. The assay utilizes mouse embryo aggregation chimeras consisting of one irradiated embryo paired with an unirradiated embryo whose blastomeres have been labeled with fluorescein isothiocyanate (FITC). X irradiation (from 0.05 to 2 Gy) and chimera construction were performed with four-cell stage embryos, and the chimeras were cultured for 40 h to the morula stage. The morulae were partially dissociated with calcium-free culture medium and viewed under phase contrast and epifluorescence microscopy to obtain total embryo cell number and the cellular contribution of irradiated (unlabeled) and control (FITC labeled) embryos per chimera. In chimeras where neither embryo was irradiated, the ratio of the unlabeled blastomeres to the total number of blastomeres per chimera embryo was 0.50 (17.8 +/- 5.6 cells per unlabeled embryo and 17.4 +/- 5.5 cells per FITC-labeled partner embryo). However, in chimeras formed after the unlabeled embryos were irradiated with as little as 0.05 Gy, the ratio of unlabeled blastomeres to the total number of blastomeres per chimera embryo was 0.43 (P less than 0.01). The apparent decreases in cell proliferation were not observed in irradiated embryos that were merely cocultured with control embryos, regardless of whether the embryos were zona enclosed or zona free. We conclude that very low levels of radiation induce sublethal changes in cleaving embryos that are expressed as a proliferative disadvantage within two cell cycles when irradiated embryos are in direct cell-to-cell contact with unirradiated embryos

The First Human Cloned Embryo.

Science.gov (United States)

Cibelli, Jose B.; Lanza, Robert P.; West, Michael D.; Ezzell, Carol

2002-01-01

Describes a process known as parthenogenesis which produces cloned, early-stage embryos and human embryos generated only from eggs. Speculates that this technology puts therapeutic cloning within reach. (DDR)

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

Science.gov (United States)

Łukaszuk, Krzysztof; Pukszta, Sebastian; Wells, Dagan; Cybulska, Celina; Liss, Joanna; Płóciennik, Łukasz; Kuczyński, Waldemar; Zabielska, Judyta

2015-04-01

To determine the usefulness of semiconductor-based next-generation sequencing (NGS) for cleavage-stage preimplantation genetic diagnosis (PGD) of aneuploidy. Prospective case-control study. A private center for reproductive medicine. 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. Choice of embryos for transfer was based on the PGD NGS results. Clinical pregnancy rate (PR) per embryo transfer (ET) was the primary outcome. Secondary outcomes were implantation and miscarriage rates. 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%). 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. ACTRN12614001035617. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Ethics of PGD: thoughts on the consequences of typing HLA in embryos.

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Edwards, R G

2004-08-01

As with so many fields of study associated with assisted human reproduction, many ethical issues are raised by the practice of preimplantation diagnosis of inherited disease (PGD). Some are part and parcel of assisted conception, e.g.the rights of human embryos in vitro and of embryologists to establish them, carry out research and discard them. Others unique to clinical PGD were discussed at an earlier meeting on PGD (Edwards et al., 2003). Recent developments in PGD are discussed briefly in this Commentary, especially the ethics of designer babies.

Evidence of Selection against Complex Mitotic-Origin Aneuploidy during Preimplantation Development

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McCoy, Rajiv C.; Demko, Zachary P.; Ryan, Allison; Banjevic, Milena; Hill, Matthew; Sigurjonsson, Styrmir; Rabinowitz, Matthew; Petrov, Dmitri A.

2015-01-01

Whole-chromosome imbalances affect over half of early human embryos and are the leading cause of pregnancy loss. While these errors frequently arise in oocyte meiosis, many such whole-chromosome abnormalities affecting cleavage-stage embryos are the result of chromosome missegregation occurring during the initial mitotic cell divisions. The first wave of zygotic genome activation at the 4–8 cell stage results in the arrest of a large proportion of embryos, the vast majority of which contain whole-chromosome abnormalities. Thus, the full spectrum of meiotic and mitotic errors can only be detected by sampling after the initial cell divisions, but prior to this selective filter. Here, we apply 24-chromosome preimplantation genetic screening (PGS) to 28,052 single-cell day-3 blastomere biopsies and 18,387 multi-cell day-5 trophectoderm biopsies from 6,366 in vitro fertilization (IVF) cycles. We precisely characterize the rates and patterns of whole-chromosome abnormalities at each developmental stage and distinguish errors of meiotic and mitotic origin without embryo disaggregation, based on informative chromosomal signatures. We show that mitotic errors frequently involve multiple chromosome losses that are not biased toward maternal or paternal homologs. This outcome is characteristic of spindle abnormalities and chaotic cell division detected in previous studies. In contrast to meiotic errors, our data also show that mitotic errors are not significantly associated with maternal age. PGS patients referred due to previous IVF failure had elevated rates of mitotic error, while patients referred due to recurrent pregnancy loss had elevated rates of meiotic error, controlling for maternal age. These results support the conclusion that mitotic error is the predominant mechanism contributing to pregnancy losses occurring prior to blastocyst formation. This high-resolution view of the full spectrum of whole-chromosome abnormalities affecting early embryos provides insight

Evidence of Selection against Complex Mitotic-Origin Aneuploidy during Preimplantation Development.

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Rajiv C McCoy

2015-10-01

Full Text Available Whole-chromosome imbalances affect over half of early human embryos and are the leading cause of pregnancy loss. While these errors frequently arise in oocyte meiosis, many such whole-chromosome abnormalities affecting cleavage-stage embryos are the result of chromosome missegregation occurring during the initial mitotic cell divisions. The first wave of zygotic genome activation at the 4-8 cell stage results in the arrest of a large proportion of embryos, the vast majority of which contain whole-chromosome abnormalities. Thus, the full spectrum of meiotic and mitotic errors can only be detected by sampling after the initial cell divisions, but prior to this selective filter. Here, we apply 24-chromosome preimplantation genetic screening (PGS to 28,052 single-cell day-3 blastomere biopsies and 18,387 multi-cell day-5 trophectoderm biopsies from 6,366 in vitro fertilization (IVF cycles. We precisely characterize the rates and patterns of whole-chromosome abnormalities at each developmental stage and distinguish errors of meiotic and mitotic origin without embryo disaggregation, based on informative chromosomal signatures. We show that mitotic errors frequently involve multiple chromosome losses that are not biased toward maternal or paternal homologs. This outcome is characteristic of spindle abnormalities and chaotic cell division detected in previous studies. In contrast to meiotic errors, our data also show that mitotic errors are not significantly associated with maternal age. PGS patients referred due to previous IVF failure had elevated rates of mitotic error, while patients referred due to recurrent pregnancy loss had elevated rates of meiotic error, controlling for maternal age. These results support the conclusion that mitotic error is the predominant mechanism contributing to pregnancy losses occurring prior to blastocyst formation. This high-resolution view of the full spectrum of whole-chromosome abnormalities affecting early embryos

Feminists on the inalienability of human embryos.

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McLeod, Carolyn; Baylis, Francoise

2006-01-01

The feminist literature against the commodification of embryos in human embryo research includes an argument to the effect that embryos are "intimately connected" to persons, or morally inalienable from them. We explore why embryos might be inalienable to persons and why feminists might find this view appealing. But, ultimately, as feminists, we reject this view because it is inconsistent with full respect for women's reproductive autonomy and with a feminist conception of persons as relational, embodied beings. Overall, feminists should avoid claims about embryos' being inalienable to persons in arguments for or against the commodification of human embryos.

Effect of early addition of bone morphogenetic protein 5 (BMP5) to embryo culture medium on in vitro development and expression of developmentally important genes in bovine preimplantation embryos.

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García, Elina V; Miceli, Dora C; Rizo, Gabriela; Valdecantos, Pablo A; Barrera, Antonio D

2015-09-01

blastocyst stage in the BMP5 group. Moreover, reverse transcription quantitative real-time polymerase chain reaction analysis showed a significant increase in the relative abundance of SOX2 in two-cell stage embryos, ID2 and OCT4 in eight-cell stage embryos, and NANOG and OCT4 in blastocysts derived from BMP5-treated embryos. In conclusion, our results report that early addition of BMP5 to the embryo culture medium had a positive effect on the blastocyst rate and affected the relative expression of BMP target and pluripotency genes, suggesting that BMP5 could play an important role in the preimplantation development of bovine embryos. Copyright © 2015 Elsevier Inc. All rights reserved.

Counselling considerations for chromosomal mosaicism detected by preimplantation genetic screening.

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Besser, Andria G; Mounts, Emily L

2017-04-01

The evolution of preimplantation genetic screening (PGS) for aneuploidy to blastocyst biopsy and more sensitive 24-chromosome screening techniques has resulted in a new diagnostic category of PGS results: those classified as mosaic. This diagnosis presents significant challenges for clinicians in developing policies regarding transfer and storage of such embryos, as well as in providing genetic counselling for patients prior to and following PGS. Given the high frequency of mosaic PGS results and the wide range of possible associated outcomes, there is an urgent need to understand how to appropriately counsel patients regarding such embryos. This is the first commentary to thoroughly address pre- and post-test genetic counselling recommendations, as well as considerations regarding prenatal screening and diagnosis. Current data on mosaic PGS results are summarized along with embryo selection considerations and potential outcomes of embryos diagnosed as mosaic. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Study of embryonic ploidy: a probable embryo model

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Kundt, Miriam S; Cabrini, Romulo L [Comision Nacional de Energia Atomica, Buenos Aires (Argentina). Dept. de Radiobiologia

2001-07-01

The second polar body (PB) studies in preimplantation mouse embryos were carried out to evaluate the possibility as reference cell to analyze ploidy. For that purpose embryos in a one cell stage [obtained by crossing hybrid females (CBAxC57BL) to NIH males] were cultured in vitro during 72 hs, individually fixed at morula stage and stained with Feulgen. The DNA content of 263 individual nucleus was evaluated cytophotometrically corresponding to 22 compact morulas of normal development. As haploid PB is present in all pre implanted stage, only embryos with one haploid nuclei were considered as normal. In 95.5% (n = 21) of the embryos the PB was present. DNA measurement of 21 PB was 1n {+-} 0.1. By the height sensibility of PB ploidy, the abnormalities were detected by the criterion of >4.1 n and <1.9 n. The results showed that one embryo was completely haploid (1n). The rest of the embryos (n = 20) 222 blastomeres and 20 PB were analyzed. The DNA measurement showed that 92,7% of the blastomeres (n = 206) are between 2 n and 4 n and 7.3% showed ploidy anomalies, regarding the value n of their PB. The period of the cellular cycle was studied in the normal cell ploidy. This study showed that 16.5% of the blastomeres (n = 34) were in the period G1, 70.39% (n =34) in the period S and 13.2% in the period G2 (n = 27). It is concluded that the PB study showed that it has properties as an excellent indicator of internal ploidia: it is present from the moment of the conception, easily recognizable in the perivitelin space in the embryo of one-two cells, remains in interface during the preimplantation development, it is haploid and digitalized pixel by pixel PB study showed the homogeneity of this type of cell, giving a reliable value of ploidy. The properties of the PB and the results showed that the PB could be an excellent indicator for embryonic ploidy studies on genotoxicity, maintaining its original ploidia during the preimplantation development while the blastomeres are

Number of blastocysts biopsied as a predictive indicator to obtain at least one normal/balanced embryo following preimplantation genetic diagnosis with single nucleotide polymorphism microarray in translocation cases.

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Wang, Yi-Zi; Ding, Chen-Hui; Wang, Jing; Zeng, Yan-Hong; Zhou, Wen; Li, Rong; Zhou, Can-Quan; Deng, Ming-Fen; Xu, Yan-Wen

2017-01-01

The aim of this study is to investigate the minimum number of blastocysts for biopsy to increase the likelihood of obtaining at least one normal/balanced embryo in preimplantation genetic diagnosis (PGD) for translocation carriers. This blinded retrospective study included 55 PGD cycles for Robertsonian translocation (RT) and 181 cycles for reciprocal translocation (rcp) to indicate when only one of the couples carried a translocation. Single-nucleotide polymorphism microarray after trophectoderm biopsy was performed. Reliable results were obtained for 355/379 (93.7 %) biopsied blastocysts in RT group and 986/1053 (93.6 %) in rcp group. Mean numbers of biopsied embryos per patient, normal/balanced embryos per patient, and mean normal/balanced embryo rate per patient were 7.4, 3.1, and 40.7 % in RT group and 8.0, 2.1, and 27.3 %, respectively, in rcp group. In a regression model, three factors significantly affected the number of genetically transferrable embryos: number of biopsied embryos (P = 0.001), basal FSH level (P = 0.040), and maternal age (P = 0.027). ROC analysis with a cutoff of 1.5 was calculated for the number of biopsied embryos required to obtain at least one normal/balanced embryo for RT carriers. For rcp carriers, the cutoff was 3.5. The clinical pregnancy rate per embryo transfer was 44.2 and 42.6 % in RT and rcp groups (P = 0.836). The minimum numbers of blastocysts to obtain at least one normal/balanced embryo for RT and rcp were 2 and 4 under the conditions of female age < 37 years with a basal FSH level < 11.4 IU/L.

Human implantation: the last barrier in assisted reproduction technologies?

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Edwards, Robert G

2006-12-01

Implantation processes are highly complex involving the actions of numerous hormones, immunoglobulins, cytokines and other factors in the endometrium. They are also essential matters for the success of assisted reproduction. The nature of early embryonic development is of equal significance. It involves ovarian follicle growth, ovulation, fertilization and preimplantation growth. These processes are affected by imbalanced chromosomal constitutions or slow developmental periods. Post-implantation death is also a significant factor in cases of placental insufficiency or recurrent abortion. Clearly, many of these matters can significantly affect birth rates. This review is concerned primarily with the oocyte, the early embryo and its chromosomal anomalies, and the nature of factors involved in implantation. These are clearly among the most important features in determining successful embryonic and fetal growth. Successive sections cover the endocrine stimulation of follicle growth in mice and humans, growth of human embryos in vitro, their apposition and attachment to the uterus, factors involved in embryo attachment to uterine epithelium and later stages of implantation, and understanding the gene control of polarities and other aspects of preimplantation embryo differentiation. New aspects of knowledge include the use of human oocyte maturation in vitro as an approach to simpler forms of IVF, and new concepts in developmental genetics.

Ethical issues in new uses of preimplantation genetic diagnosis: should parents be allowed to use preimplantation genetic diagnosis to choose the sexual orientation of their children?

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Dahl, Edgar

2003-07-01

Extending the application of preimplantation genetic diagnosis (PGD) to screen embryos for non-medical traits such as gender, height and intelligence, raises serious moral, legal, and social issues. In this paper I consider the possibility of using PGD to select the sexual orientation of offspring. After considering five potential objections, I conclude that parents should be permitted to use PGD to choose the sexual orientation of their children.

Ethanol impedes embryo transport and impairs oviduct epithelium

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Xu, Tonghui; Yang, Qiuhong; Liu, Ruoxi; Wang, Wenfu; Wang, Shuanglian; Liu, Chuanyong; Li, Jingxin

2016-01-01

Most studies have demonstrated that alcohol consumption is associated with decreased fertility. The aim of this study was to investigate the effects of alcohol on pre-implantation embryo transport and/or early embryo development in the oviduct. We reported here that ethanol concentration-dependently suppressed the spontaneous motility of isolated human oviduct strips (EC50 50 ± 6 mM), which was largely attenuated in the present of L-NAME, a classical nitric oxide synthase(NOS) competitive inhibitor. Notably, either acute or chronic alcohol intake delayed egg transport and retarded early development of the embryo in the mouse oviduct, which was largely rescued by co-administration of L-NAME in a acute alcohol intake group but not in chronic alcohol intake group. It is worth mentioning that the oviductal epithelium destruction was verified by scanning electron microscope (SEM) observations in chronic alcohol intake group. In conclusion, alcohol intake delayed egg transport and retarded early development of the embryo in the oviduct by suppressing the spontaneous motility of oviduct and/or impairing oviductal epithelium. These findings suggested that alcohol abuse increases the incident of ectopic pregnancy.

Ethanol impedes embryo transport and impairs oviduct epithelium.

Science.gov (United States)

Xu, Tonghui; Yang, Qiuhong; Liu, Ruoxi; Wang, Wenfu; Wang, Shuanglian; Liu, Chuanyong; Li, Jingxin

2016-05-16

Most studies have demonstrated that alcohol consumption is associated with decreased fertility. The aim of this study was to investigate the effects of alcohol on pre-implantation embryo transport and/or early embryo development in the oviduct. We reported here that ethanol concentration-dependently suppressed the spontaneous motility of isolated human oviduct strips (EC50 50±6mM), which was largely attenuated in the present of L-NAME, a classical nitric oxide synthase(NOS) competitive inhibitor. Notably, either acute or chronic alcohol intake delayed egg transport and retarded early development of the embryo in the mouse oviduct, which was largely rescued by co-administration of L-NAME in a acute alcohol intake group but not in chronic alcohol intake group. It is worth mentioning that the oviductal epithelium destruction was verified by scanning electron microscope (SEM) observations in chronic alcohol intake group. In conclusion, alcohol intake delayed egg transport and retarded early development of the embryo in the oviduct by suppressing the spontaneous motility of oviduct and/or impairing oviductal epithelium. These findings suggested that alcohol abuse increases the incident of ectopic pregnancy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Preimplantation HLA typing for stem cell transplantation treatment of hemoglobinopathies

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Anver Kuliev

2014-09-01

Full Text Available Preimplantation genetic diagnosis (PGD for HLA typing is steadily becoming an option for at risk couples with thalassemic children, requiring HLA matched bone marrow transplantation treatment. The paper presents the world’s largest PGD experience of 475 cases for over 2 dozens thalassemia mutations, resulting in birth of 132 unaffected children. A total of 146 cases were performed together with preimplantation HLA typing, resulting in detection and transfer of HLA matched unaffected embryos in 83 of them, yielding the birth of 16 HLA matched children, potential donors for their affected siblings. The presented experience of HLA matched stem cell transplantation for thalassemia, following PGD demonstrated a successful hematopoietic reconstitution both for younger and older patients. The data show that PGD is an efficient approach for HLA matched stem cell transplantation treatment for thalassemia.

45,X product of conception after preimplantation genetic diagnosis and euploid embryo transfer: evidence of a spontaneous conception confirmed by DNA fingerprinting.

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Bettio, Daniela; Capalbo, Antonio; Albani, Elena; Rienzi, Laura; Achille, Valentina; Venci, Anna; Ubaldi, Filippo Maria; Levi Setti, Paolo Emanuele

2016-09-06

Preimplantation genetic screening (PGS) provides an opportunity to eliminate a potential implantation failure due to aneuploidy in infertile couples. Some studies clearly show that twins following single embryo transfer (SET) can be the result of a concurrent natural conception and an incidence as high as 1 in 5 twins has been reported. In our case PGS was performed on trophectoderm (TE) biopsies by quantitative polymerase chain reaction (qPCR). The product of conception (POC) was cytogenetically investigated after selection of the placental villi by means of the direct method. Molecular cytogenetic characterization of the POC was performed by fluorescence in situ hybridization (FISH) and array-comparative genomic hybridization (a-CGH) analyses. To investigate the possibility of a spontaneous conception, a panel of 40 single nucleotide polymorphisms (SNPs) was used to compare genetic similarity between the DNA of the POC and the DNA leftover of the TE biopsy. We describe a 36-year old infertile woman undergoing PGS who had a spontaneous abortion after a single euploid embryo transfer on a spontaneous cycle. The POC showed a 45,X karyotype confirmed by FISH and a-CGH. DNA fingerprinting demonstrated a genetic similarity of 75 % between the DNA of the POC and TE biopsy, consistent with a sibling status. All supernumerary euploid embryos were also tested showing a non-self relationship with the POC, excluding a mix-up event at the time of fetal embryo transfer. DNA fingerprinting of the transferred blastocyst and POC, confirmed the occurrence of a spontaneous conception. This case challenges the assumption that a pregnancy after assisted reproductive technology (ART) is always a result of ART, and strengthens the importance to avoid intercourses during PGS and natural transfer cycles. Moreover, cytogenetic analysis of the POCs is strongly recommended along with fingerprinting children born after PGS to see what the concordance is between the embryo transferred and

Preimplantation genetic diagnosis for mitochondrial DNA mutations: analysis of one blastomere suffices.

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Sallevelt, Suzanne C E H; Dreesen, Joseph C F M; Coonen, Edith; Paulussen, Aimee D C; Hellebrekers, Debby M E I; de Die-Smulders, Christine E M; Smeets, Hubert J M; Lindsey, Patrick

2017-10-01

Preimplantation genetic diagnosis (PGD) is a reproductive strategy for mitochondrial DNA (mtDNA) mutation carriers, strongly reducing their risk of affected offspring. Embryos either without the mutation or with mutation load below the phenotypic threshold are transferred to the uterus. Because of incidental heteroplasmy deviations in single blastomere and the relatively limited data available, we so far preferred relying on two blastomeres rather than one. Considering the negative effect of a two-blastomere biopsy protocol compared with a single-blastomere biopsy protocol on live birth delivery rate, we re-evaluated the error rate in our current dataset. For the m.3243A>G mutation, sufficient embryos/blastomeres were available for a powerful analysis. The diagnostic error rate, defined as a potential false-negative result, based on a threshold of 15%, was determined in 294 single blastomeres analysed in 73 embryos of 9 female m.3243A>G mutation carriers. Only one out of 294 single blastomeres (0.34%) would have resulted in a false-negative diagnosis. False-positive diagnoses were not detected. Our findings support a single-blastomere biopsy PGD protocol for the m.3243A>G mutation as the diagnostic error rate is very low. As in the early preimplantation embryo no mtDNA replication seems to occur and the mtDNA is divided randomly among the daughter cells, we conclude this result to be independent of the specific mutation and therefore applicable to all mtDNA mutations. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Choosing between possible lives: legal and ethical issues in preimplantation genetic diagnosis.

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Scott, Rosamund

2006-01-01

This article critically appraises the current legal scope of the principal applications of preimplantation genetic diagnosis (PGD). This relatively new technique, which is available to some parents undergoing in vitro fertilization (IVF) treatment, aims to ensure that a child is not born with a seemingly undesirable genetic condition. The question addressed here is whether there should be serious reasons to test for genetic conditions in embryos in order to be able to select between them. The Human Fertilisation and Embryology Authority and the Human Genetics Commission have decided that there should be such reasons by broadly aligning the criteria for PGD with those for selective abortion. This stance is critically explored, as are its implications for the possible use of PGD to select either against or for marginal features or for significant traits. The government is currently reviewing the legal scope and regulation of PGD.

[Unaffected child born following preimplantation genetic diagnosis with karyomapping].

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Nánássy, László; Téglás, Gyöngyvér; Csenki, Marianna; Vereczkey, Attila

2016-12-01

Preimplantation genetic diagnosis for single gene defects is a well established method in assisted reproductive technologies. Karyomapping is a genome wide parental haplotyping using a high density single nucleotide polymorphism array that allows the diagnosis of any single gene defects. A couple with an affected child with primary congenital glaucoma attended at our clinic. Six oocyte-cumulus-complex was retrieved and all three mature oocytes were inseminated. One zygote showed the signs of normal fertilization and was cultured for five days. Trophectoderm biopsy and karyomapping analysis were carried out. Result showed a heterozygous carrier for primary congenital glaucoma. Embryo was thawed and transferred and a healthy girl was delivered at term. Here we report the first live birth following in vitro fertilization combined with preimplantation genetic diagnosis using karyomapping in Hungary. Karyomapping is able to accurately detect single gene disorders from a limited amount of samples without a significant preclinical workup. Orv. Hetil., 2016, 157(51), 2048-2050.

EXPERIMENTAL TRIES TO ESTABLISH THE PREIMPLANTATIONAL MAMMALIAN EMBRYOS VIABILITY THROUGHOUT STAINING

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IVAN ALEXANDRA

2007-01-01

Full Text Available Presently there are more methods to assess embryo quality but, still the wieldy usedremains the morphological criteria method. In this experiment were tested twostaining methods for embryos and oocytes. The embryos were recovered from mousefemale at 72 hours after mating. The recovered embryos were first evaluated aftermorphological criteria and than by Trypan blue exclusion and Neutral red staining.Using Trypan blue exclusion were evaluated 30 embryos from which 19 (63.3 wereclassified as viable and 11 (36.7 were classified as nonviable. By Neutral redstaining were evaluated 37 embryos from which 24 (64.8 were considered viableand 13 (35.2 were considered nonviable. The oocytes recovered were alsoevaluated using the two methods: using Trypan blue exclusion were stained 10oocytes from which 9 remained uncolored and were considered viable and 1 wasstained in blue and was considered nonviable and using Neutral red 13 oocytes werestained from which 9 were evaluated as viable and 4 as nonviable.

Capturing Human Naïve Pluripotency in the Embryo and in the Dish.

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Zimmerlin, Ludovic; Park, Tea Soon; Zambidis, Elias T

2017-08-15

Although human embryonic stem cells (hESCs) were first derived almost 20 years ago, it was only recently acknowledged that they share closer molecular and functional identity to postimplantation lineage-primed murine epiblast stem cells than to naïve preimplantation inner cell mass-derived mouse ESCs (mESCs). A myriad of transcriptional, epigenetic, biochemical, and metabolic attributes have now been described that distinguish naïve and primed pluripotent states in both rodents and humans. Conventional hESCs and human induced pluripotent stem cells (hiPSCs) appear to lack many of the defining hallmarks of naïve mESCs. These include important features of the naïve ground state murine epiblast, such as an open epigenetic architecture, reduced lineage-primed gene expression, and chimera and germline competence following injection into a recipient blastocyst-stage embryo. Several transgenic and chemical methods were recently reported that appear to revert conventional human PSCs to mESC-like ground states. However, it remains unclear if subtle deviations in global transcription, cell signaling dependencies, and extent of epigenetic/metabolic shifts in these various human naïve-reverted pluripotent states represent true functional differences or alternatively the existence of distinct human pluripotent states along a spectrum. In this study, we review the current understanding and developmental features of various human pluripotency-associated phenotypes and discuss potential biological mechanisms that may support stable maintenance of an authentic epiblast-like ground state of human pluripotency.

Interspecific in vitro assay for the chimera-forming ability of human pluripotent stem cells.

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Masaki, Hideki; Kato-Itoh, Megumi; Umino, Ayumi; Sato, Hideyuki; Hamanaka, Sanae; Kobayashi, Toshihiro; Yamaguchi, Tomoyuki; Nishimura, Ken; Ohtaka, Manami; Nakanishi, Mahito; Nakauchi, Hiromitsu

2015-09-15

Functional assay limitations are an emerging issue in characterizing human pluripotent stem cells (PSCs). With rodent PSCs, chimera formation using pre-implantation embryos is the gold-standard assay of pluripotency (competence of progeny to differentiate into all three germ layers). In human PSCs (hPSCs), however, this can only be monitored via teratoma formation or in vitro differentiation, as ethical concerns preclude generation of human-human or human-animal chimeras. To circumvent this issue, we developed a functional assay utilizing interspecific blastocyst injection and in vitro culture (interspecies in vitro chimera assay) that enables the development and observation of embryos up to headfold stage. The assay uses mouse pre-implantation embryos and rat, monkey and human PSCs to create interspecies chimeras cultured in vitro to the early egg-cylinder stage. Intra- and interspecific chimera assays with rodent PSC lines were performed to confirm the consistency of results in vitro and in vivo. The behavior of chimeras developed in vitro appeared to recapitulate that of chimeras developed in vivo; that is, PSC-derived cells survived and were integrated into the epiblast of egg-cylinder-stage embryos. This indicates that the interspecific in vitro chimera assay is useful in evaluating the chimera-forming ability of rodent PSCs. However, when human induced PSCs (both conventional and naïve-like types) were injected into mouse embryos and cultured, some human cells survived but were segregated; unlike epiblast-stage rodent PSCs, they never integrated into the epiblast of egg-cylinder-stage embryos. These data suggest that the mouse-human interspecies in vitro chimera assay does not accurately reflect the early developmental potential/process of hPSCs. The use of evolutionarily more closely related species as host embryos might be necessary to evaluate the developmental potency of hPSCs. © 2015. Published by The Company of Biologists Ltd.

What Drives Embryo Development? Chromosomal Normality or Mitochondria?

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A. Bayram

2017-01-01

Full Text Available Objective. To report the arrest of euploid embryos with high mtDNA content. Design. A report of 2 cases. Setting. Private fertility clinic. Patients. 2 patients, 45 and 40 years old undergoing IVF treatment. Interventions. Mature oocytes were collected and vitrified from two ovarian stimulations. Postthaw, survived mature oocytes underwent fertilization by intracytoplasmic sperm injection (ICSI. Preimplantation genetic screening (PGS and mitochondrial DNA (mtDNA copy number were done using next generation sequencing (NGS. The only normal embryo among the all-biopsied embryos had the highest “Mitoscore” value and was the only arrested embryo in both cases. Therefore, the embryo transfer was cancelled. Main Outcome Measures. Postthaw survival and fertilization rate, embryo euploidy, mtDNA copy number, and embryo development. Results. In both patients, after PGS only 1 embryo was euploid. Both embryos had the highest mtDNA copy number from all tested embryos and both embryos were arrested on further development. Conclusions. These cases clearly demonstrate the lack of correlation between mtDNA value (Mitoscore and chromosomal status of embryo.

Preimplantation genetic diagnosis (PGD) for HLA typing: bases for setting up an open international collaboration when PGD is not available.

Science.gov (United States)

Bellavia, Marina; Von Der Weid, Nicolas; Peddes, Christina; Jacquemont, Sebastien; Liebaers, Inge; Hohlfeld, Patrick; Wunder-Galié, Dorothea; de Ziegler, Dominique

2010-08-01

In severe forms of Diamond-Blackfan anemia, preimplantation genetic diagnosis (PGD) of histocompatibility leukocyte antigen-compatible embryos for enabling the next sibling in the family to be a stem-cell transplantation donor constitutes the sole lasting cure capable of terminating the enduring need for iterative transfusions. We report here an open collaboration between two renowned institutions to provide a family desiring this treatment even though they resided where the preimplantation genetic diagnosis procedure is banned. Copyright (c) 2010 American Society for Reproductive Medicine. All rights reserved.

Comprehensive embryo testing. Experts' opinions regarding future directions: an expert panel study on comprehensive embryo testing.

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Hens, Kristien; Dondorp, Wybo J; Geraedts, Joep P M; de Wert, Guido M

2013-05-01

What do scientists in the field of preimplantation genetic diagnosis (PGD) and preimplantation genetic screening (PGS) consider to be the future direction of comprehensive embryo testing? Although there are many biological and technical limitations, as well as uncertainties regarding the meaning of genetic variation, comprehensive embryo testing will impact the IVF/PGD practice and a timely ethical reflection is needed. Comprehensive testing using microarrays is currently being introduced in the context of PGD and PGS, and it is to be expected that whole-genome sequencing will also follow. Current ethical and empirical sociological research on embryo testing focuses on PGD as it is practiced now. However, empirical research and systematic reflection regarding the impact of comprehensive techniques for embryo testing is missing. In order to understand the potential of this technology and to be able to adequately foresee its implications, we held an expert panel with seven pioneers in PGD. We conducted an expert panel in October 2011 with seven PGD pioneers from Belgium, The Netherlands, Germany and the UK. Participants expected the use of comprehensive techniques in the context of PGD. However, the introduction of these techniques in embryo testing requires timely ethical reflection as it involves a shift from choosing an embryo without a particular genetic disease (i.e. PGD) or most likely to result in a successful pregnancy (i.e. PGS) to choosing the best embryo based on a much wider set of criteria. Such ethical reflection should take account of current technical and biological limitations and also of current uncertainties with regard to the meaning of genetic variance. However, ethicists should also not be afraid to look into the future. There was a general agreement that embryo testing will be increasingly preceded by comprehensive preconception screening, thus enabling smart combinations of genetic testing. The group was composed of seven participants from

The Influence of Single Nucleotide Polymorphism Microarray-Based Molecular Karyotype on Preimplantation Embryonic Development Potential.

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Gang Li

Full Text Available In order to investigate the influence of the molecular karyotype based on single nucleotide polymorphism (SNP microarray on embryonic development potential in preimplantation genetic diagnosis (PGD, we retrospectively analyzed the clinical data generated by PGD using embryos retrieved from parents with chromosome rearrangements in our center. In total, 929 embryos from 119 couples had exact diagnosis and development status. The blastocyst formation rate of balanced molecular karyotype embryos was 56.6% (276/488, which was significantly higher than that of genetic imbalanced embryos 24.5% (108/441 (P35 respectively. Blastocyst formation rates of male and female embryos were 44.5% (183/411 and 38.8% (201/518 respectively, with no significant difference between them (P>0.05. The rates of balanced molecular karyotype embryos vary from groups of embryos with different cell numbers at 68 hours after insemination. The blastocyst formation rate of embryos with 6-8 cells (48.1% was significantly higher than that of embryos with 8 cells (42.9% (P8 cells, embryos with 6-8 blastomeres have higher rate of balanced molecular karyotype and blastocyst formation.

Antigen presenting cells costimulatory signaling during pre-implantation pregnancy 

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Anna Sławek

2012-09-01

Full Text Available  Success of pregnancy depends on many factors. Three phenomena inducing immune tolerance against semi-allogeneic conceptus may play a crucial role in the pre-implantation period of pregnancy: influence of sex hormones in sex cycle, presence of oocyte or embryo and the presence of semen in the female reproductive tract. On the other hand dendritic cells are the most effective antigen-presenting cells in regulation of immune phenomena and also are considered as potent participants in inducing immune tolerance in the pregnancy. They communicate with T cells in cell contact-dependent manner or via cytokines. During cell-cell contacts, costimulatory molecules play a key role and their expression is often dependent on cytokines milieu. Both costimulatory molecules and cytokines influence generation of T regulatory cells. Interactions of these molecules are closely related. In this paper we would like to pay attention to the importance of antigen presenting cells costimulatory potency in immune regulation during a pre-implantation period of pregnancy.

Study on preimplantation genetic diagnosis and follow-up for Duchenne muscular dystrophy

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Juan YANG

2015-07-01

Full Text Available Objective  To carry out preimplantation genetic diagnosis (PGD for Duchenne muscular dystrophy (DMD carrier, so as to prevent the birth of affected infants with DMD.  Methods  One DMD gene carrier with a deletion of exon 10-30 received fertilization with intracytoplasmic sperm injection (ICSI. DMD gene and haplotype were tested after amplification of genome DNA in multiple displacement amplification (MDA, then healthy embryos were transferred to uterus according to the genetic results. Genetic testing was made in second trimester and after delivery, and also periodic follow-up was made for over 3 years.  Results  The second cycle of PGD was successful, and a total of 14 single blastomeres obtained from 7 embryos were used for genetic analysis. The success rate of MDA was 13/14, and the allele dropout rate was 18.75% (18/96. Three unaffected embryos were transferred, resulting in twin pregnancy. One healthy boy and one healthy girl were born in cesarean section at the pregnant week of 35. Genetic results on DNA from both amniotic fluid at 16 weeks of gestation and peripheral blood after birth were normal. During the 3-year follow-up, both 2 infants were normal in growth and development, motor function and dynamic monitor of serum creatine kinase (CK.  Conclusions  Preimplantation genetic diagnosis can help DMD gene carrier give birth to healthy infants, and these infants have normal development. DOI: 10.3969/j.issn.1672-6731.2015.06.008

Simultaneous preimplantation genetic diagnosis for Tay-Sachs and Gaucher disease.

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Altarescu, Gheona; Brooks, Barry; Margalioth, Ehud; Eldar Geva, Talia; Levy-Lahad, Ephrat; Renbaum, Paul

2007-07-01

Preimplantation genetic diagnosis (PGD) for single gene defects is described for a family in which each parent is a carrier of both Tay-Sachs (TS) and Gaucher disease (GD). A multiplex fluorescent polymerase chain reaction protocol was developed that simultaneously amplified all four familial mutations and 10 informative microsatellite markers. In one PGD cycle, seven blastomeres were analysed, reaching a conclusive diagnosis in six out of seven embryos for TS and in five out of seven embryos for GD. Of the six diagnosed embryos, one was wild type for both TS and GD, and three were wild type for GD and carriers of TS. Two remaining embryos were compound heterozygotes for TS. Two transferable embryos developed into blastocysts (wt/wt and wt GD/carrier TS) and both were transferred on day 5. This single cycle of PGD resulted in a healthy live child. Allele drop-out (ADO) was observed in three of 34 reactions, yielding an 8% ADO rate. The occurrence of ADO in single cell analysis and undetected recombination events are primary causes of misdiagnosis in PGD and emphasize the need to use multiple polymorphic markers. So far as is known, this is the first report of concomitant PGD for two frequent Ashkenazi Jewish recessive disorders.

[Extending preimplantation genetic diagnosis to HLA typing: the French exception].

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Steffann, Julie; Frydman, Nelly; Burlet, Philippe; Gigarel, Nadine; Hesters, Laetitia; Kerbrat, Violaine; Lamazou, Frédéric; Munnich, Arnold; Frydman, René

2011-01-01

Umut-Talha, a "sibling savior", was born on 26 January 2011 at Beclère Hospital after embryo selection at the Paris preimplantation genetic diagnosis (PGD) center. His birth revived the controversy over "double PGD". This procedure, authorized in France since 2006, allows couples who already have a child with a serious, incurable genetic disease, to opt for PGD in order to select a healthy embryo that is HLA-matched to the affected sibling and who may thus serve as an ombilical cord blood donor. The procedure is particularly complex and the baby take-home rate is still very low. Double PGD is strictly regulated in France, and candidate couples must first receive individual authorization from the Biomedicine Agency. In our experience, these couples have a strong desire to have children, as reflected by the large number of prior spontaneous pregnancies (25% of couples). Likewise, most of these couples request embryo transfer even when there is no HLA-matched embryo, which accounts for more than half of embryo transfers. The controversy surrounding this practice has flared up again in recent weeks, over the concepts of "designer babies" and "double savior siblings" (the baby is selected to be free of the hereditary disease, and may also serve as a stem cell donor for the affected sibling).

Hot Topic: Preimplantation aneuploidy screening

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Kayhan Yakın

2009-03-01

Full Text Available Preimplantation Genetic Screening (PGS is a technique that has been introduced into clinical practice to screen and eliminate aneuploid embryos form transfer with the intention to improve implantation rates and decrease pregnancy wastage. Although practiced widely throughout the world the PGS unfortunately has been adopted without being subjected to rigorous scientific validation. Data from recent prospective randomized trials have shed doubt on the efficacy of the procedure when used in women with advanced age, one of the target populations for PGS. Other purported indications for the application of this complicated technique such as recurrent implantation failure and recurrent spontaneous abortion have not been subjected to randomized controlled trials. For the best interest of patients, we feel it is timely for a debate regarding the efficacy and safety of PGS.

Lipofection of siRNA into bovine 8-16-cell stage embryos using zona removal and the well-of-the-well culture system.

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Ikeda, Shuntaro; Sugimoto, Miki; Kume, Shinichi

2018-04-13

Bovine preimplantation embryos exhibit dramatic biological changes between before and after the 8-16-cell stage. Here we report a simple lipofection method to transfect siRNA into bovine 8-16-cell stage embryos using zona removal and the well-of-the-well (WOW) culture system. Bovine one-cell embryos produced in vitro were freed from the zona pellucida and cultured up to the 8-16-cell stage in WOW dishes. The 8-16-cell embryos were lipofected with siRNA and the transfection efficiency was assessed at 48 h of transfection. Lipofection with a red fluorescent non-targeting siRNA revealed the importance of zona removal for transfection of siRNA into embryos. Using this method, we knocked down the methionine adenosyltransferase 2A (MAT2A) gene, achieving a significant reduction in MAT2A expression (P lipofection', may be useful to analyze gene functions in bovine preimplantation embryos without expensive equipment and skill-intensive techniques.

In vitro production of small ruminant embryos: late improvements and further research.

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de Souza-Fabjan, Joanna Maria Gonçalves; Panneau, Barbara; Duffard, Nicolas; Locatelli, Yann; de Figueiredo, José Ricardo; Freitas, Vicente José de Figueirêdo; Mermillod, Pascal

2014-06-01

Beyond the potential use of in vitro production of embryos (IVP) in breeding schemes, embryos are also required for the establishment of new biotechnologies such as cloning and transgenesis. Additionally, the knowledge of oocyte and embryo physiology acquired through IVP techniques may stimulate the further development of other techniques such as marker assisted and genomic selection of preimplantation embryos, and also benefit assisted procreation in human beings. Efficient in vitro embryo production is currently a major objective for livestock industries, including small ruminants. The heterogeneity of oocytes collected from growing follicles by laparoscopic ovum pick up or in ovaries of slaughtered females, remains an enormous challenge for IVM success, and still limits the rate of embryo development. In addition, the lower quality of the IVP embryos, compared with their in vivo-derived counterparts, translates into poor cryosurvival, which restricts the wider use of this promising technology. Therefore, many studies have been reported in an attempt to determine the most suitable conditions for IVM, IVF, and in vitro development to maximize embryo production rate and quality. This review aims to present the current panorama of IVP production in small ruminants, describing important steps for its success, reporting the recent advances and also the main obstacles identified for its improvement and dissemination. Copyright © 2014 Elsevier Inc. All rights reserved.

Birth of healthy children after preimplantation diagnosis of β-thalassemia

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焦泽旭; 庄广伦; 周灿权; 舒益民; 李洁; 梁晓燕

2004-01-01

Background Clinical programs for preventing β-thalassemia are presently based on prospective carrier screening and prenatal diagnosis. This paper report an achievement of a pregnancy with unaffected embryos using in vitro fertilization and embryo transfer (IVF-ET), in combination with preimplantation genetic diagnosis (PGD), for a couple at risk of having children with β-thalassemia.Methods A couple carrying different thalassemia mutations, both a codon 41-42 mutation and the IVS Ⅱ 654 mutation, received standard IVF treatment, with intracytoplasmic sperm injection, embryo biopsiy, single cell polymerase chain reaction (PCR) and DNA analysis. Only unaffected or carrier embryos were transferred to the uterine cavity. After confirmation of pregnancy, a prenatal diagnosis was performed.Results Of a total of 13 embryos analyzed for β-globin mutations, PGD indicated that 2 were normal,3 were affected, and 6 were carriers. Diagnosis could not be made in the other 2 embryos. Three embryos were transferred to the uterus on the third day after oocyte retrieval. Ultrasonography revealed a twin pregnancy with one blighted ovum. The prenatal genetic diagnosis revealed that both fetuses were unaffected, and two healthy boys were born, confirming the results of PGD.Conclusions We developed a single-cell based primer extension preamplification (PEP)-PCR assay for the detection of β-thalassemia mutations. The assays were efficient and accurate at all stages of the procedure, and resulted in the birth of PGD-confirmed β-thalassemia free children in China. PEP was used here in PGD for β-thalassemia.

The use of embryonic stem cell derived bioactive material as a new protein supplement for the in vitro culture of bovine embryos.

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Kim, Eun Young; Lee, Jun Beom; Park, Hyo Young; Jeong, Chang Jin; Riu, Key Zung; Park, Se Pill

2011-06-01

Embryonic stem (ES) cells are expanded versions of the inner cell mass cells that compose the early mammalian blastocyst. Components derived from ES cells may contain various bioactive materials (BM) helpful for early preimplantation embryo growth. In this study, we examined the effect of human ES cell derived BM (hES-BM) on in vitro culture of bovine embryos. When bovine parthenogenetic day 2 embryos were cultured in 10% hES-BM, a significantly higher embryo development rate (44.3%) and increased cell numbers were observed relative to control medium containing 3 mg/ml BSA (19.5%; Pculture environment to support the growth of bovine embryos in vitro (P<0.05). Little difference was observed between 10% hES-BM and 10% FBS treatment in the examined parthenogenetic or in vitro fertilized embryos, although the hES-BM group developed at a slightly better rate. However, the ICM cell numbers were significantly higher in the hES-BM group in irrespective of embryo origin (P<0.05). In addition, the relative levels of pluripotency (Oct4, × 1.8 fold; Nanog. × 3.3 fold), embryogenesis (Stat3, × 2.8 fold; FGF4, × 18.8 fold; E-cad, × 2.0 fold) and growth (Glut5, × 2.6 fold) genes were significantly higher in the 10% hES-BM group than in the 10% FBS group (P<0.05), while the levels of other genes (Bax, Bcl2, MnSOD and Connexin43) were not different. This is the first report examining the positive effects of hES-BM on bovine embryo development in vitro. Based on our results, we conclude that hES-BM can be used as a new protein supplement for bovine preimplantation embryo development.

Obesity does not aggravate vitrification injury in mouse embryos: a prospective study

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Ma Wenhong

2012-08-01

Full Text Available Abstract Background Obesity is associated with poor reproductive outcomes, but few reports have examined thawed embryo transfer in obese women. Many studies have shown that increased lipid accumulation aggravates vitrification injury in porcine and bovine embryos, but oocytes of these species have high lipid contents (63 ng and 161 ng, respectively. Almost nothing is known about lipids in human oocytes except that these cells are anecdotally known to be relatively lipid poor. In this regard, human oocytes are considered to be similar to those of the mouse, which contain approximately 4 ng total lipids/oocyte. To date, no available data show the impact of obesity on vitrification in mouse embryos. The aim of this study was to establish a murine model of maternal diet-induced obesity and to characterize the effect of obesity on vitrification by investigating the survival rate and embryo developmental competence after thawing. Methods Prospective comparisons were performed between six–eight-cell embryos from obese and normal-weight mice and between fresh and vitrified embryos. Female C57BL/6 mice were fed standard rodent chow (normal-weight group or a high-fat diet (obese group for 6 weeks. The mice were mated, zygotes were collected from oviducts and cultured for 3 days, and six–eight-cell embryos were then selected to assess lipid content in fresh embryos and to evaluate differences in apoptosis, survival, and development rates in response to vitrification. Results In fresh embryos from obese mice, the lipid content (0.044 vs 0.030, Pvs.9.3%, Pvs. 93.1%, P Conclusions This study demonstrated that differences in survival and developmental rates between embryos from obese and normal-weight mice were eliminated after vitrification. Thus, maternal obesity does not aggravate vitrification injury, but obesity alone greatly impairs pre-implantation embryo survival and development.

Comparative study of single-nucleotide polymorphism array and next generation sequencing based strategies on triploid identification in preimplantation genetic diagnosis and screen.

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Xu, Jiawei; Niu, Wenbin; Peng, Zhaofeng; Bao, Xiao; Zhang, Meixiang; Wang, Linlin; Du, Linqing; Zhang, Nan; Sun, Yingpu

2016-12-06

Triploidy occurred about 2-3% in human pregnancies and contributed to approximately 15% of chromosomally caused human early miscarriage. It is essential for preimplantation genetic diagnosis and screen to distinct triploidy sensitively. Here, we performed comparative investigations between MALBAC-NGS and MDA-SNP array sensitivity on triploidy detection. Self-correction and reference-correction algorism were used to analyze the NGS data. We identified 5 triploid embryos in 1198 embryos of 218 PGD and PGS cycles using MDA-SNP array, the rate of tripoidy was 4.17‰ in PGS and PGD patients. Our results indicated that the MDA-SNP array was sensitive to digyny and diandry triploidy, MALBAC-NGS combined with self and reference genome correction strategies analyze were not sensitive to detect triploidy. Our study demonstrated that triploidy occurred at 4.17‰ in PGD and PGS, MDA-SNP array could successfully identify triploidy in PGD and PGS and genomic DNA. MALBAC-NGS combined with self and reference genome correction strategies were not sensitive to triploidy.

In vitro culture of individual mouse preimplantation embryos: the role of embryo density, microwells, oxygen, timing and conditioned media.

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Kelley, Rebecca L; Gardner, David K

2017-05-01

Single embryo culture is suboptimal compared with group culture, but necessary for embryo monitoring, and culture systems should be improved for single embryos. Pronucleate mouse embryos were used to assess the effect of culture conditions on single embryo development. Single culture either before or after compaction reduced cell numbers (112.2 ± 3.1; 110.2 ± 3.5) compared with group culture throughout (127.0 ± 3.4; P media volume from 20 µl to 2 µl increased blastocyst cell numbers in single embryos cultured in 5% oxygen (84.4 ± 3.2 versus 97.8 ± 2.8; P Culture in microwell plates for the EmbryoScope and Primo Vision time-lapse systems changed cleavage timings and increased inner cell mass cell number (24.1 ± 1.0; 23.4 ± 1.2) compared with a 2 µl microdrop (18.4 ± 1.0; P media to single embryos increased hatching rate and blastocyst cell number (91.5 ± 4.7 versus 113.1 ± 4.4; P culture before or after compaction is therefore detrimental; oxygen, media volume and microwells influence single embryo development; and embryo-conditioned media may substitute for group culture. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

De novo DNA methylation during monkey pre-implantation embryogenesis.

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Gao, Fei; Niu, Yuyu; Sun, Yi Eve; Lu, Hanlin; Chen, Yongchang; Li, Siguang; Kang, Yu; Luo, Yuping; Si, Chenyang; Yu, Juehua; Li, Chang; Sun, Nianqin; Si, Wei; Wang, Hong; Ji, Weizhi; Tan, Tao

2017-04-01

Critical epigenetic regulation of primate embryogenesis entails DNA methylome changes. Here we report genome-wide composition, patterning, and stage-specific dynamics of DNA methylation in pre-implantation rhesus monkey embryos as well as male and female gametes studied using an optimized tagmentation-based whole-genome bisulfite sequencing method. We show that upon fertilization, both paternal and maternal genomes undergo active DNA demethylation, and genome-wide de novo DNA methylation is also initiated in the same period. By the 8-cell stage, remethylation becomes more pronounced than demethylation, resulting in an increase in global DNA methylation. Promoters of genes associated with oxidative phosphorylation are preferentially remethylated at the 8-cell stage, suggesting that this mode of energy metabolism may not be favored. Unlike in rodents, X chromosome inactivation is not observed during monkey pre-implantation development. Our study provides the first comprehensive illustration of the 'wax and wane' phases of DNA methylation dynamics. Most importantly, our DNA methyltransferase loss-of-function analysis indicates that DNA methylation influences early monkey embryogenesis.

Human embryo research and the 14-day rule.

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Pera, Martin F

2017-06-01

In many jurisdictions, restrictions prohibit the culture of human embryos beyond 14 days of development. However, recent reports describing the successful maintenance of embryos in vitro to this stage have prompted many in the field to question whether the rule is still appropriate. This Spotlight article looks at the original rationale behind the 14-day rule and its relevance today in light of advances in human embryo culture and in the derivation of embryonic-like structures from human pluripotent stem cells. © 2017. Published by The Company of Biologists Ltd.

Laser confers less embryo exposure than acid tyrode for embryo biopsy in preimplantation genetic diagnosis cycles: a randomized study.

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Geber, Selmo; Bossi, Renata; Lisboa, Cintia B; Valle, Marcelo; Sampaio, Marcos

2011-04-28

We compared two methods of zona pellucida drilling. 213 embryos were biopsied with acid Tyrode. Each biopsy took 3 minutes and the entire procedure ~29 minutes. 5% of blastomeres lysed, 49% of embryos became blastocyst and 36% of patients became pregnant. 229 embryos were biopsied with laser. Each biopsy took 30 seconds and the entire procedure ~7 minutes. 2.5% of blastomeres lysed, 50.6% of embryos became blastocyst and 47% of patients became pregnant. We can conclude that laser can be used for embryo biopsy. Reduction of embryo exposure and of removed blastomeres is associated with increased blastocysts available for transfer and a better clinical outcome.

Laser confers less embryo exposure than acid tyrode for embryo biopsy in preimplantation genetic diagnosis cycles: a randomized study

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Valle Marcelo

2011-04-01

Full Text Available Abstract We compared two methods of zona pellucida drilling. 213 embryos were biopsied with acid Tyrode. Each biopsy took 3 minutes and the entire procedure ~29 minutes. 5% of blastomeres lysed, 49% of embryos became blastocyst and 36% of patients became pregnant. 229 embryos were biopsied with laser. Each biopsy took 30 seconds and the entire procedure ~7 minutes. 2.5% of blastomeres lysed, 50.6% of embryos became blastocyst and 47% of patients became pregnant. We can conclude that laser can be used for embryo biopsy. Reduction of embryo exposure and of removed blastomeres is associated with increased blastocysts available for transfer and a better clinical outcome.

Embryo transcriptome response to environmental factors: implication for its survival under suboptimal conditions.

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Salilew-Wondim, Dessie; Tesfaye, Dawit; Hoelker, Michael; Schellander, Karl

2014-09-01

After its formation, the mammalian zygote undergoes a series of morphological, physiological and biochemical alterations prior to undergoing cell differentiation. The zygote is then transformed into a complex multicellular organism in a defined time window which may differ between species. These orderly embryonic developmental events are tightly regulated by temporal and spatial activation and/or deactivation of genes and gene products. This phenomenon may in turn be dependent on the intrinsic characteristics of the embryo itself, the physiological and biochemical composition of the maternal environment or by in vitro culture condition. In fact, when embryos are subjected to suboptimal culture condition, some of the embryos may escape the environmental stress by activating certain transcripts and some others which are unable to activate anti-stress agents may die or exhibit abnormal development. This phenomenon may partly depend on transcripts and proteins stored during oogenesis. Indeed after embryonic genome activation, the embryo destiny is governed by its own transcripts and protein synthesized over time. Therefore, this review begins by highlighting the type and quality of transcripts accumulated or degraded during oogenesis and its impact on the embryo survival. Thereafter, emphasis is given to the transcriptome response of preimplantation embryos to suboptimal culture conditions. In addition, the long term effect of preimplantation culture environment on the transcriptome response embryos/fetus during peri and post implantation has been addressed. Finally, a brief summary of the epigenetic control of culture induced genetic variation of the embryos has been highlighted. Copyright © 2014 Elsevier B.V. All rights reserved.

Trichostatin A (TSA) improves the development of rabbit-rabbit intraspecies cloned embryos, but not rabbit-human interspecies cloned embryos.

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Shi, Li-Hong; Miao, Yi-Liang; Ouyang, Ying-Chun; Huang, Jun-Cheng; Lei, Zi-Li; Yang, Ji-Wen; Han, Zhi-Ming; Song, Xiang-Fen; Sun, Qing-Yuan; Chen, Da-Yuan

2008-03-01

The interspecies somatic cell nuclear transfer (iSCNT) technique for therapeutic cloning gives great promise for treatment of many human diseases. However, the incomplete nuclear reprogramming and the low blastocyst rate of iSCNT are still big problems. Herein, we observed the effect of TSA on the development of rabbit-rabbit intraspecies and rabbit-human interspecies cloned embryos. After treatment with TSA for 6 hr during activation, we found that the blastocyst rate of rabbit-rabbit cloned embryos was more than two times higher than that of untreated embryos; however, the blastocyst rate of TSA-treated rabbit-human interspecies cloned embryos decreased. We also found evident time-dependent histone deacetylation-reacetylation changes in rabbit-rabbit cloned embryos, but not in rabbit-human cloned embryos from fusion to 6 hr after activation. Our results suggest that TSA-treatment does not improve blastocyst development of rabbit-human iSCNT embryos and that abnormal histone deacetylation-reacetylation changes in iSCNT embryos may account for their poor blastocyst development. (c) 2008 Wiley-Liss, Inc.

Sourcing human embryos for embryonic stem cell lines: Problems & perspectives

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Rajvi H Mehta

2014-01-01

Full Text Available The ability to successfully derive human embryonic stem cells (hESC lines from human embryos following in vitro fertilization (IVF opened up a plethora of potential applications of this technique. These cell lines could have been successfully used to increase our understanding of human developmental biology, transplantation medicine and the emerging science of regenerative medicine. The main source for human embryos has been ′discarded′ or ′spare′ fresh or frozen human embryos following IVF. It is a common practice to stimulate the ovaries of women undergoing any of the assisted reproductive technologies (ART and retrieve multiple oocytes which subsequently lead to multiple embryos. Of these, only two or maximum of three embryos are transferred while the rest are cryopreserved as per the decision of the couple. In case a couple does not desire to ′cryopreserve′ their embryos then all the embryos remaining following embryo transfer can be considered ′spare′ or if a couple is no longer in need of the ′cryopreserved′ embryos then these also can be considered as ′spare′. But, the question raised by the ethicists is, "what about ′slightly′ over-stimulating a woman to get a few extra eggs and embryos? The decision becomes more difficult when it comes to ′discarded′ embryos. As of today, the quality of the embryos is primarily assessed based on morphology and the rate of development mainly judged by single point assessment. Despite many criteria described in the literature, the quality assessment is purely subjective. The question that arises is on the decision of ′discarding′ embryos. What would be the criteria for discarding embryos and the potential ′use′ of ESC derived from the ′abnormal appearing′ embryos? This paper discusses some of the newer methods to procure embryos for the derivation of embryonic stem cell lines which will respect the ethical concerns but still provide the source material.

Imprinted Expression of SNRPN in Human Preimplantation Embryos

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Huntriss, John; Daniels, Robert; Bolton, Virginia; Monk, Marilyn

1998-01-01

Prader-Willi syndrome (PWS) and Angelman syndrome (AS) are two clinically distinct neurogenetic disorders arising from a loss of expression of imprinted genes within the human chromosome region 15q11-q13. Recent evidence suggests that the SNRPN gene, which is defective in PWS, plays a central role in the imprinting-center regulation of the PWS/AS region. To increase our understanding of the regulation of expression of this imprinted gene, we have developed single-cell-sensitive procedures for...

Preimplantation genetic diagnosis and rational choice under risk or uncertainty.

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Zuradzki, Tomasz

2014-11-01

In this paper I present an argument in favour of a parental duty to use preimplantation genetic diagnosis (PGD). I argue that if embryos created in vitro were able to decide for themselves in a rational manner, they would sometimes choose PGD as a method of selection. Couples, therefore, should respect their hypothetical choices on a principle similar to that of patient autonomy. My thesis shows that no matter which moral doctrine couples subscribe to, they ought to conduct the PGD procedure in the situations when it is impossible to implant all of the created embryos and if there is a significant risk for giving birth to a child with a serious condition. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Cryopreservation of Embryos and Oocytes in Human Assisted Reproduction

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János Konc

2014-01-01

Full Text Available Both sperm and embryo cryopreservation have become routine procedures in human assisted reproduction and oocyte cryopreservation is being introduced into clinical practice and is getting more and more widely used. Embryo cryopreservation has decreased the number of fresh embryo transfers and maximized the effectiveness of the IVF cycle. The data shows that women who had transfers of fresh and frozen embryos obtained 8% additional births by using their cryopreserved embryos. Oocyte cryopreservation offers more advantages compared to embryo freezing, such as fertility preservation in women at risk of losing fertility due to oncological treatment or chronic disease, egg donation, and postponing childbirth, and eliminates religious and/or other ethical, legal, and moral concerns of embryo freezing. In this review, the basic principles, methodology, and practical experiences as well as safety and other aspects concerning slow cooling and ultrarapid cooling (vitrification of human embryos and oocytes are summarized.

Cryopreservation of embryos and oocytes in human assisted reproduction.

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Konc, János; Kanyó, Katalin; Kriston, Rita; Somoskői, Bence; Cseh, Sándor

2014-01-01

Both sperm and embryo cryopreservation have become routine procedures in human assisted reproduction and oocyte cryopreservation is being introduced into clinical practice and is getting more and more widely used. Embryo cryopreservation has decreased the number of fresh embryo transfers and maximized the effectiveness of the IVF cycle. The data shows that women who had transfers of fresh and frozen embryos obtained 8% additional births by using their cryopreserved embryos. Oocyte cryopreservation offers more advantages compared to embryo freezing, such as fertility preservation in women at risk of losing fertility due to oncological treatment or chronic disease, egg donation, and postponing childbirth, and eliminates religious and/or other ethical, legal, and moral concerns of embryo freezing. In this review, the basic principles, methodology, and practical experiences as well as safety and other aspects concerning slow cooling and ultrarapid cooling (vitrification) of human embryos and oocytes are summarized.

Effect of Bacterial Endotoxins on Superovulated Mouse Embryos In Vivo: Is CSF-1 Involved in Endotoxin-Induced Pregnancy Loss?

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Yogesh Kumar Jaiswal

2006-01-01

Full Text Available Mammalian embryonic development is regulated by several cytokines and growth factors from embryonic or maternal origins. Since CSF-1 plays important role in embryonic development and implantation, we investigated its role in gram-negative bacterial LPS-induced implantation failure. The effect of LPS on normal (nonsuperovulated and superovulated in vivo-produced embryos was assessed by signs of morphological degeneration. A significantly similar number of morphologically degenerated embryos recovered from both nonsuperovulated and superovulated LPS treated animals on day 2.5 of pregnancy onwards were morphologically and developmentally abnormal as compared to their respective controls (P < .001. Normal CSF-1 expression level and pattern were also altered through the preimplantation period in the mouse embryos and uterine horns after LPS treatment. This deviation from the normal pattern and level of CSF-1 expression in the preimplantation embryos and uterine tissues suggest a role for CSF-1 in LPS-induced implantation failure.

Utilization of endogenous fatty acid stores for energy production in bovine preimplantation embryos.

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Sutton-McDowall, Melanie L; Feil, Deanne; Robker, Rebecca L; Thompson, Jeremy G; Dunning, Kylie R

2012-05-01

Although current embryo culture media are based on carbohydrate metabolism of embryos, little is known about metabolism of endogenous lipids. L-carnitine is a β-oxidation cofactor absent in most culture media. The objective was to investigate the influence of L-carnitine supplementation on bovine embryo development. Abattoir-derived bovine cumulus oocyte complexes were cultured and fertilized. Post-fertilization, presumptive zygotes were transferred into a basic cleavage medium ± carbohydrates (glucose, lactate and pyruvate) ± 5 mm L-carnitine and cultured for 4 days in vitro. In the absence of carbohydrates during culture, embryos arrested at the 2- and 4-cell stages. Remarkably, +L-carnitine increased development to the morula stage compared to +carbohydrates alone (P levels were higher and ATP: ADP ratio were 1.9-fold lower (main effect, P < 0.05) compared to embryos cultured in -L-carnitine. Therefore, we inferred that +L-carnitine embryos were more metabolically active, with higher rates of ATP-ADP conversion. In conclusion, L-carnitine supplementation supported precompaction embryo development and there was an additive effect of +L-carnitine +carbohydrates on early embryo development, most likely through increased β-oxidation within embryos. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

Physiology and culture of the human blastocyst.

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Gardner, David K; Lane, Michelle; Schoolcraft, William B

2002-01-01

The human embryo undergoes many changes in physiology during the first 4 days of life as it develops and differentiates from a fertilized oocyte to the blastocyst stage. Concomitantly, the embryo is exposed to gradients of nutrients within the female reproductive tract and exhibits changes in its own nutrient requirements and utilization. Determining the nature of such nutrient gradients in the female tract and the changing requirements of the embryo has facilitated the formulation of stage-specific culture media designed to support embryo development throughout the preimplantation period. Resultant implantation rates attained with the culture and transfer of human blastocysts are higher than those associated with the transfer of cleavage stage embryos to the uterus. Such increases in implantation rates have facilitated the establishment of high pregnancy rates while reducing the number of embryos transferred. With the introduction of new scoring systems for the blastocyst and the non-invasive assessment of metabolic activity of individual embryos, it should be possible to move to single blastocyst transfer for the majority of patients.

[Advance in the methods of preimplantation genetic diagnosis for single gene diseases].

Science.gov (United States)

Ren, Yixin; Qiao, Jie; Yan, Liying

2017-06-10

More than 7000 single gene diseases have been identified and most of them lack effective treatment. As an early form of prenatal diagnosis, preimplantation genetic diagnosis (PGD) is a combination of in vitro fertilization and genetic diagnosis. PGD has been applied in clinics for more than 20 years to avoid the transmission of genetic defects through analysis of embryos at early stages of development. In this paper, a review for the recent advances in PGD for single gene diseases is provided.

Blood pressure and anthropometrics of 4-y-old children born after preimplantation genetic screening: follow-up of a unique, moderately sized, randomized controlled trial

NARCIS (Netherlands)

Seggers, Jorien; Haadsma, Maaike L.; Bastide-van Gemert, Sacha la; Heineman, Maas Jan; Kok, Joke H.; Middelburg, Karin J.; Roseboom, Tessa J.; Schendelaar, Pamela; van den Heuvel, Edwin R.; Hadders-Algra, Mijna

2013-01-01

Recent studies suggest that in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) are associated with suboptimal cardiometabolic outcome in offspring. It is unknown whether preimplantation genetic screening (PGS), which involves embryo biopsy, affects blood pressure (BP),

Blood pressure and anthropometrics of 4-y-old children born after preimplantation genetic screening : follow-up of a unique, moderately sized, randomized controlled trial

NARCIS (Netherlands)

Seggers, Jorien; Haadsma, Maaike L.; la Bastide-van Gemert, Sacha; Heineman, Maas Jan; Kok, Joke H.; Middelburg, Karin J.; Roseboom, Tessa J.; Schendelaar, Pamela; Van den Heuvel, Edwin R.; Hadders-Algra, Mijna

2013-01-01

BACKGROUND: Recent studies suggest that in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) are associated with suboptimal cardiometabolic outcome in offspring. It is unknown whether preimplantation genetic screening (PGS), which involves embryo biopsy, affects blood pressure

RESEARCHES REGARDING THE INFLUENCE OF RECOVERY MEDIA ON THE IN VITRO DEVELOPMENT CAPACITY OF THE PREIMPLANTATIONAL MOUSE EMBRYO

Directory of Open Access Journals (Sweden)

ADA CEAN

2009-05-01

Full Text Available Phosphate Bufered Saline with 0.4% BSA and M2 medium are one of the most common media used in embryorecovery. The aim of our paper was to investigate if the recovery media used for the recovery of the mouseembryo is influencing in vitro developmental capacity. As biological material we used 10 used were mousefemales, age 2 months superovulated with 5UI PMSG (Pregnant Mare Serum Gonadotropine and 5 UI hCG(human Corionic Gonadotropine. The embryos used were recovered, by oviduct flushing, at 24 hours from theidentification of the vaginal plug. The majority of the embryos (78.3% were in two cells stage. A total of 123, 2cells embryos were cultivated in M16 medium. The evolution of the embryos was examined at 24, 48 and 72hours interval. The proportion of hatched blastocyst was higher at the embryos recovered with M2 (53.7%compared with the embryos recovered with PBS 0.4% BSA. The difference is statistically very significant(p<0.001. Embryos recovered in M2 media have a higher in vitro developmental capacity compared with theembryos recovered in PBS media supplemented with 0,4% BSA, possibly because of the sodium bicarbonate andlactate used in M2 media for pH regulation.

Prediction of in-vitro developmental competence of early cleavage-stage mouse embryos with compact time-lapse equipment.

Science.gov (United States)

Pribenszky, Csaba; Losonczi, Eszter; Molnár, Miklós; Lang, Zsolt; Mátyás, Szabolcs; Rajczy, Klára; Molnár, Katalin; Kovács, Péter; Nagy, Péter; Conceicao, Jason; Vajta, Gábor

2010-03-01

Single blastocyst transfer is regarded as an efficient way to achieve high pregnancy rates and to avoid multiple pregnancies. Risk of cancellation of transfer due to a lack of available embryos may be reduced by early prediction of blastocyst development. Time-lapse investigation of mouse embryos shows that the time of the first and second cleavage (to the 2- and 3-cell stages, respectively) has a strong predictive value for further development in vitro, while cleavage from the 3-cell to the 4-cell stage has no predictive value. In humans, embryo fragmentation during preimplantation development has been associated with lower pregnancy rates and a higher incidence of developmental abnormalities. Analysis of time-lapse records shows that most fragmentation is reversible in the mouse and is resorbed in an average of 9 h. Daily or bi-daily microscopic checks of embryo development, applied routinely in human IVF laboratories, would fail to detect 36 or 72% of these fragmentations, respectively. Fragmentation occurring in a defined time frame has a strong predictive value for in-vitro embryo development. The practical compact system used in the present trial, based on the 'one camera per patient' principle, has eliminated the usual disadvantages of time-lapse investigations and is applicable for the routine follow-up of in-vitro embryo development. Copyright 2009 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Practices and ethical concerns regarding preimplantation diagnosis. Who regulates preimplantation genetic diagnosis in Brazil?

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B.B. Damian

2015-01-01

Full Text Available Preimplantation genetic diagnosis (PGD was originally developed to diagnose embryo-related genetic abnormalities for couples who present a high risk of a specific inherited disorder. Because this technology involves embryo selection, the medical, bioethical, and legal implications of the technique have been debated, particularly when it is used to select features that are not related to serious diseases. Although several initiatives have attempted to achieve regulatory harmonization, the diversity of healthcare services available and the presence of cultural differences have hampered attempts to achieve this goal. Thus, in different countries, the provision of PGD and regulatory frameworks reflect the perceptions of scientific groups, legislators, and society regarding this technology. In Brazil, several texts have been analyzed by the National Congress to regulate the use of assisted reproduction technologies. Legislative debates, however, are not conclusive, and limited information has been published on how PGD is specifically regulated. The country requires the development of new regulatory standards to ensure adequate access to this technology and to guarantee its safe practice. This study examined official documents published on PGD regulation in Brazil and demonstrated how little direct oversight of PGD currently exists. It provides relevant information to encourage reflection on a particular regulation model in a Brazilian context, and should serve as part of the basis to enable further reform of the clinical practice of PGD in the country.

Influence of the radiation (Co60) in pre-implants rabbit embryos: effect on atypic mitotic index and embryo pole development

International Nuclear Information System (INIS)

Approbato, Mario S.; Oliveira Moura, Katia K.V. de; Souza Florencio, Rodopiano de; Garcia, Ricardo; Faria, Renato S.; Benedetti, Leonardo N.; Goulart, Flamarion B.

1995-01-01

We studied the effect of ionizing irradiation on 12 New Zealand rabbits (65 embryos), at three different times: at match time (zero hour), two days after and four days after, with two different irradiation doses: five c Gy and ten c Gy. Six rabbits (36 blastocysts) were used as controls. the matching instant was the zero hour. Exactly six days after (± 60 minutes) the embryos of each rabbit was picked up by flushing the uterus with culture media. the embryos were fixed in methanol for 48 hours, and colored with acid Mayer hematoxylin. The following embryo parameters were studied: embryo pole development; percentage of abnormal mitotic figures. irradiation time was associated with lower scores of embryo pole development, but not with irradiation dose. There were no gross abnormalities of embryo pole. The abnormal mitotic cells was affected both by the time and dose of irradiation. (author)

Quantitative imaging of lipids in live mouse oocytes and early embryos using CARS microscopy

Science.gov (United States)

Bradley, Josephine; Pope, Iestyn; Masia, Francesco; Sanusi, Randa; Langbein, Wolfgang; Borri, Paola

2016-01-01

Mammalian oocytes contain lipid droplets that are a store of fatty acids, whose metabolism plays a substantial role in pre-implantation development. Fluorescent staining has previously been used to image lipid droplets in mammalian oocytes and embryos, but this method is not quantitative and often incompatible with live cell imaging and subsequent development. Here we have applied chemically specific, label-free coherent anti-Stokes Raman scattering (CARS) microscopy to mouse oocytes and pre-implantation embryos. We show that CARS imaging can quantify the size, number and spatial distribution of lipid droplets in living mouse oocytes and embryos up to the blastocyst stage. Notably, it can be used in a way that does not compromise oocyte maturation or embryo development. We have also correlated CARS with two-photon fluorescence microscopy simultaneously acquired using fluorescent lipid probes on fixed samples, and found only a partial degree of correlation, depending on the lipid probe, clearly exemplifying the limitation of lipid labelling. In addition, we show that differences in the chemical composition of lipid droplets in living oocytes matured in media supplemented with different saturated and unsaturated fatty acids can be detected using CARS hyperspectral imaging. These results demonstrate that CARS microscopy provides a novel non-invasive method of quantifying lipid content, type and spatial distribution with sub-micron resolution in living mammalian oocytes and embryos. PMID:27151947

Recent advances in preimplantation genetic diagnosis and screening.

Science.gov (United States)

Lu, Lina; Lv, Bo; Huang, Kevin; Xue, Zhigang; Zhu, Xianmin; Fan, Guoping

2016-09-01

Preimplantation genetic diagnosis/screening (PGD/PGS) aims to help couples lower the risks of transmitting genetic defects to their offspring, implantation failure, and/or miscarriage during in vitro fertilization (IVF) cycles. However, it is still being debated with regard to the practicality and diagnostic accuracy of PGD/PGS due to the concern of invasive biopsy and the potential mosaicism of embryos. Recently, several non-invasive and high-throughput assays have been developed to help overcome the challenges encountered in the conventional invasive biopsy and low-throughput analysis in PGD/PGS. In this mini-review, we will summarize the recent progresses of these new methods for PGD/PGS and discuss their potential applications in IVF clinics.

Chromosome segregation analysis in human embryos obtained from couples involving male carriers of reciprocal or Robertsonian translocation.

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Ahmet Yilmaz

Full Text Available The objective of this study was to investigate the frequency and type of chromosome segregation patterns in cleavage stage embryos obtained from male carriers of Robertsonian (ROB and reciprocal (REC translocations undergoing preimplantation genetic diagnosis (PGD at our reproductive center. We used FISH to analyze chromosome segregation in 308 day 3 cleavage stage embryos obtained from 26 patients. The percentage of embryos consistent with normal or balanced segregation (55.1% vs. 27.1% and clinical pregnancy (62.5% vs. 19.2% rates were higher in ROB than the REC translocation carriers. Involvement of non-acrocentric chromosome(s or terminal breakpoint(s in reciprocal translocations was associated with an increase in the percent of embryos consistent with adjacent 1 but with a decrease in 3∶1 segregation. Similar results were obtained in the analysis of nontransferred embryos donated for research. 3∶1 segregation was the most frequent segregation type in both day 3 (31% and spare (35% embryos obtained from carriers of t(11;22(q23;q11, the only non-random REC with the same breakpoint reported in a large number of unrelated families mainly identified by the birth of a child with derivative chromosome 22. These results suggest that chromosome segregation patterns in day 3 and nontransferred embryos obtained from male translocation carriers vary with the type of translocation and involvement of acrocentric chromosome(s or terminal breakpoint(s. These results should be helpful in estimating reproductive success in translocation carriers undergoing PGD.

Persons and their bodies: how we should think about human embryos.

Science.gov (United States)

McLachlan, Hugh V

2002-01-01

The status of human embryos is discussed particularly in the light of the claim by Fox, in Health Care Analysis 8 that it would be useful to think of them in terms of cyborg metaphors. It is argued that we should consider human embryos for what they are--partially formed human bodies--rather than for what they are like in some respects (and unlike in others)--cyborgs. However to settle the issue of the status of the embryo is not to answer the moral questions which arise concerning how embryos should be treated. Since persons rather than bodies have rights, embryos do not have rights. However, whether or not embryos have rights, people can have duties concerning them. Furthermore, the persons whose fully developed bodies embryos will, might (or might have) become can have rights. Contrary to what is often assumed, it is not merely persons who have (or have had) living, developed human bodies who have moral rights: so it is argued in this paper.

Derivation of Two New Human Embryonic Stem Cell Lines from Nonviable Human Embryos

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Svetlana Gavrilov

2011-01-01

Full Text Available We report the derivation and characterization of two new human embryonic stem cells (hESC lines (CU1 and CU2 from embryos with an irreversible loss of integrated organismic function. In addition, we analyzed retrospective data of morphological progression from embryonic day (ED 5 to ED6 for 2480 embryos not suitable for clinical use to assess grading criteria indicative of loss of viability on ED5. Our analysis indicated that a large proportion of in vitro fertilization (IVF embryos not suitable for clinical use could be used for hESC derivation. Based on these combined findings, we propose that criteria commonly used in IVF clinics to determine optimal embryos for uterine transfer can be employed to predict the potential for hESC derivation from poor quality embryos without the destruction of vital human embryos.

Chromosomal mosaicism in mouse two-cell embryos after paternal exposure to acrylamide

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Marchetti, Francesco; Bishop, Jack; Lowe, Xiu; Wyrobek, Andrew J

2008-10-14

Chromosomal mosaicism in human preimplantation embryos is a common cause ofspontaneous abortions, however, our knowledge of its etiology is limited. We used multicolor fluorescence in situ hybridization (FISH) painting to investigate whether paternally-transmitted chromosomal aberrations result in mosaicism in mouse 2-cell embryos. Paternal exposure to acrylamide, an important industrial chemical also found in tobacco smoke and generated during the cooking process of starchy foods, produced significant increases in chromosomally defective 2-cell embryos, however, the effects were transient primarily affecting the postmeiotic stages of spermatogenesis. Comparisons with our previous study of zygotes demonstrated similar frequencies of chromosomally abnormal zygotes and 2-cell embryos suggesting that there was no apparent selection against numerical or structural chromosomal aberrations. However, the majority of affected 2-cell embryos were mosaics showing different chromosomal abnormalities in the two blastomeric metaphases. Analyses of chromosomal aberrations in zygotes and 2-cell embryos showed a tendency for loss of acentric fragments during the first mitotic division ofembryogenesis, while both dicentrics and translocations apparently underwent propersegregation. These results suggest that embryonic development can proceed up to the end of the second cell cycle of development in the presence of abnormal paternal chromosomes and that even dicentrics can persist through cell division. The high incidence of chromosomally mosaic 2-cell embryos suggests that the first mitotic division of embryogenesis is prone to missegregation errors and that paternally-transmitted chromosomal abnromalities increase the risk of missegregation leading to embryonic mosaicism.

[Association of human chorionic gonadotropin level in embryo culture media with early embryo development].

Science.gov (United States)

Wang, Haiying; Zhang, Renli; Han, Dong; Liu, Caixia; Cai, Jiajie; Bi, Yanling; Wen, Anmin; Quan, Song

2014-06-01

To investigate the association of human chorionic gonadotropin (HCG) level on day 3 of embryo culture with embryo development. Spent culture media were collected from individually cultured embryos on day 3 of in vitro fertilization and embryo transfer (IVF-ET) cycles. HCG concentration in the culture media was measured using an ELISA kit and its association with embryo development was assessed. In the 163 samples of embryo culture media from 60 patients, HCG was positive in 153 sample (93.8%) with a mean level of 0.85 ± 0.43 mIU/ml. The concentration of hCG in the culture media increased gradually as the number of blastomeres increased (F=2.273, P=0.03), and decreased as the morphological grade of the embryo was lowered (F=3.900, P=0.02). ELISA is capable of detecting HCG levels in spent culture media of embryos on day 3 of in vitro culture. The concentration of HCG in spent culture media is positively correlated with the status of early embryo development and implantation rate and thus serves as a useful marker for embryo selection in IVF-ET procedure.

Proteomic analysis of the early bovine yolk sac fluid and cells from the day 13 ovoid and elongated preimplatation embryos

DEFF Research Database (Denmark)

Jensen, Pernille L.; Beck, Hans Christian; Petersen, Tonny S.

2014-01-01

differentiate into the hypoblast and epiblast, which remain surrounded by the trophectoderm. The formation of the hypoblast epithelium is also accompanied by a change in the fluid within the embryo, i.e., the blastocoel fluid gradually alters to become the primitive yolk sac (YS) fluid. Our previous research......The bovine blastocyst hatches 8 to 9 days after fertilization, and this is followed by several days of preimplantation development during which the embryo transforms from a spherical over an ovoid to an elongated shape. As the spherical embryo enlarges, the cells of the inner cell mass...... describes the protein composition of human and bovine blastocoel fluid, which is surrounded by the trophectoderm and undifferentiated cells of the inner cell mass. In this study, we further examine the changes in the protein composition in both the primitive YS fluid and the embryonic cells during early...

Influence of irradiation (Co60) in pre-implant rabbits embryos: effect on blastocyst diameters and embryos smaller than 2 mm

International Nuclear Information System (INIS)

Approbato, Mario S.; Oliveira Moura, Katia K.V. de; Souza Florencio, Rodopiano de; Cunha Junior, Carlos; Garcia, Ricardo; Faria, Renato S.; Benedetti, Leonardo N.; Goulart, Flamarion B.

1995-01-01

We studied the effect of ionizing irradiation on 12 New Zealand rabbits (65 embryos), in three different times: at match time (zero hour), two days after and four days after, with two different irradiation doses, 5 c Gy and 10 c Gy. Six rabbits (36 blastocysts) were used as controls. The matching instant was the zero hour. Exactly six days after (± 60 minutes) the embryos of each rabbit was picked up by flushing the uterus with culture media. The embryos were fixed in methanol for 48 hours, and colored with acid Mayer hematoxylin. The following embryos parameters were studied: diameter growth; percentage of embryos smaller than 2 mm. We observed that only the irradiation time influenced the blastocysts diameter (no irradiation dose). There was no relation between percentage of embryos smaller than 2 mm and the irradiation. (author)

Use of preimplantation genetic diagnosis and preimplantation genetic screening in the United States: a Society for Assisted Reproductive Technology Writing Group paper.

Science.gov (United States)

Ginsburg, Elizabeth S; Baker, Valerie L; Racowsky, Catherine; Wantman, Ethan; Goldfarb, James; Stern, Judy E

2011-10-01

To comprehensively report Society for Assisted Reproductive Technology (SART) member program usage of preimplantation genetic testing (PGT), preimplantation genetic diagnosis (PGD) for diagnosis of specific conditions, and preimplantation genetic screening for aneuploidy (PGS). Retrospective study. United States SART cohort data. Women undergoing a PGT cycle in which at least one embryo underwent biopsy. PGT. PGT use, indications, and delivery rates. Of 190,260 fresh, nondonor assisted reproductive technology (ART) cycles reported to SART CORS in 2007-2008, 8,337 included PGT. Of 6,971 cycles with a defined indication, 1,382 cycles were for genetic diagnosis, 3,645 for aneuploidy screening (PGS), 527 for translocation, and 1,417 for elective sex election. Although the total number of fresh, autologous cycles increased by 3.6% from 2007 to 2008, the percentage of cycles with PGT decreased by 5.8% (4,293 in 2007 and 4,044 in 2008). As a percentage of fresh, nondonor ART cycles, use dropped from 4.6% (4,293/93,433) in 2007 to 4.2% (4,044/96,827) in 2008. The primary indication for PGT was PGS: cycles performed for this indication decreased (-8.0%). PGD use for single-gene defects (+3.2%), elective sex selection (+5.3%), and translocation analysis (+0.5%) increased. PGT usage varied significantly by geographical region. PGT usage in the United States decreased between 2007 and 2008 owing to a decrease in PGS. Use of elective sex selection increased. High transfer cancellation rates correlated with reduced live-birth rates for some PGT indications. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Neonatal outcome after preimplantation genetic diagnosis.

Science.gov (United States)

Eldar-Geva, Talia; Srebnik, Naama; Altarescu, Gheona; Varshaver, Irit; Brooks, Baruch; Levy-Lahad, Ephrat; Bromiker, Ruben; Schimmel, Michael S

2014-10-01

To examine whether embryo biopsy for preimplantation genetic diagnosis (PGD) influences neonatal outcomes. Prospective follow-up cohort. Tertiary university-affiliated medical center. 242 children born after PGD, 242 children born after intracytoplasmic sperm injection (ICSI) (158 singletons and 42 twins pairs in each group), and 733 children born after a spontaneous conception (SC) (493 singletons, 120 twins pairs), matched for maternal age, parity, and body mass index. None. Gestational age, birth weight, prematurity (<37 and <34 weeks), low birth weight (<2,500 g, very low birth weight, <1,500 g), and intrauterine growth restriction (<10th percentile for gestational age). For singletons, the mean birth weight was higher after SC compared with ICSI but not compared with PGD. Mean gestational ages were lower after PGD and ICSI compared with SC. The low birth weight and intrauterine growth restriction rates were 4.4%, 12.0%, and 5.7% and 5.1%, 9.5%, and 5.5% for PGD, ICSI, and SC, respectively. Similar results were found when controlled for the number of embryos transferred and cryopreservation. The results for twins exhibited similar but less statistically significant trends. Polar body and blastomere biopsies provided similar outcomes. Embryo biopsy itself did not cause intrauterine growth restriction or low birth weight compared with SC, despite lower gestational ages with PGD. The worsened outcomes in ICSI compared with PGD pregnancies may be due to the infertility itself. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Theory about the Embryo Cryo-Treatment.

Science.gov (United States)

Vladimirov, Iavor K; Tacheva, Desislava; Diez, Antonio

2017-04-01

To create hypothesis, which can give a logical explanation related to the benefits of freezing/thawing embryos. Cryopreservation is not only a technology used for storing embryos, but also a method of embryo treatment that can potentially improve the success rate in infertile couples. From the analysis of multiple results in assisted reproductive technology, which have no satisfactory explanation to date, we found evidence to support a 'therapeutic' effect of the freezing/thawing of embryos on the process of recovery of the embryo and its subsequent implantation. Freezing/thawing is a way to activate the endogenous survival and repair responses in preimplantation embryos. Several molecular mechanisms can explain the higher success rate of ET using thawed embryos compared to fresh ET in women of advanced reproductive age, the higher miscarriage rate in cases of thawed blastocyst ET compared to thawed ET at early cleavage embryo, and the higher perinatal parameters of born children after thawed ET. Embryo thawing induces a stress. Controlled stress is not necessarily detrimental, because it generates a phenomenon that is counteracted by several known biological responses aimed to repair mitochondrial damage of membrane and protein misfolding. The term for favorable biological responses to low exposures to stress is called hormesis. This thesis will summarize the role of cryopreservation in the activation of a hormetic response, preserving the mitochondrial function, improving survival, and having an impact on the process of implantation, miscarriage, and the development of pregnancy.

Preimplantation genetic diagnosis for gender selection in the United States

Energy Technology Data Exchange (ETDEWEB)

Colls, P.; Silver, L.; Olivera, G.; Weier, J.; Escudero, T.; Goodall, N.; Tomkin, G.; Munne, S.

2009-08-20

Preimplantation genetic diagnosis (PGD) of gender selection for non medical reasons has been considered an unethical procedure by several authors and agencies in the Western society on the basis of disrupting the sex ratio, being discriminatory againsts women and disposal of normal embryos of the non desired gender. In this study, the analysis of a large series of PGD procedures for gender selection from a wide geographical area in the United States, shows that in general there is no deviation in preference towards any specific gender except for a preference of males in some ethnic populations of Chinese, Indian and Middle Eastern origin that represent a small percentage of the US population. In cases where only normal embryos of the non-desired gender are available, 45.5% of the couples elect to cancel the transfer, while 54.5% of them are open to have transferred embryos of the non-desired gender, this fact being strongly linked to cultural and ethnical background of the parents. In addition this study adds some evidence to the proposition that in couples with previous children of a given gender there is no biological predisposition towards producing embryos of that same gender. Based on these facts, it seems that objections to gender selection formulated by ethics committees and scientific societies are not well-founded.

The evidence base regarding the experiences of and attitudes to preimplantation genetic diagnosis in prospective parents.

Science.gov (United States)

Cunningham, Jenny; Goldsmith, Lesley; Skirton, Heather

2015-02-01

Preimplantation genetic diagnosis was developed as an alternative to prenatal diagnosis for couples with a family history of genetic disease. After in vitro fertilization, the embryos can be analysed to ensure that only healthy embryos are transferred to the uterus. Past studies have suggested that couples who wish to avoid having a child with an inherited genetic condition look favourably on preimplantation genetic diagnosis as it prevents the need for termination of pregnancy following prenatal diagnosis of an affected fetus. However, it is important to understand the experiences of couples who have used or consider using this technique. To ascertain the current evidence base on this topic, we conducted a mixed methods systematic review. Four databases were searched for relevant peer-reviewed papers published between 2000 and 2013. Of 453 papers, nine satisfied the inclusion criteria and were assessed for quality. Results of nine papers were analysed and synthesised using a narrative approach. Three main themes emerged: (1) motivating factors; (2) emotional labour; (3) choices and uncertainty. The review has identified an emotional and difficult journey for couples pursuing preimplantation genetic diagnosis. While use of the technique gives hope to families who wish to prevent transmission of a genetic disease this is not without hard decision-making and periods of uncertainty. Lack of information was perceived as a barrier to access this reproductive option. Recommendations include: training and education in genetics for midwives who are the first point of contact for pregnant women; clinics to use a decision-making tool to emphasise the uncertainty involved in PGD and improved communication and psychological support to couples. Copyright © 2014 Elsevier Ltd. All rights reserved.

Mitochondrial DNA content in embryo culture medium is significantly associated with human embryo fragmentation.

Science.gov (United States)

Stigliani, S; Anserini, P; Venturini, P L; Scaruffi, P

2013-10-01

Is the amount of cell-free DNA released by human embryos into culture medium correlated with embryo morphological features? The mitochondrial DNA (mtDNA) content of culture medium is significantly associated with the fragmentation rate on Days 2 and 3 of embryo development, whether the oocyte came from women ≤ 35 or >35 years old. Cellular fragmentation is often utilized as one of the morphological parameters for embryo quality assessment. The amount of cellular fragments is considered to be an important morphological parameter for embryo implantation potential. It has been hypothesized that fragments are apoptotic bodies or anuclear cytoplasmatic pieces of blastomeres, although no definitive conclusion has been drawn about their pathogenesis. Human fertilized oocytes were individually cultured from Day 1 to Days 2 and 3. A total of 800 samples (166 spent media from Day 2 and 634 from Day 3) were enrolled into the present study. Double-stranded DNA (dsDNA) was quantified in 800 spent embryo culture media by Pico Green dye fluorescence assay. After DNA purification, genomic DNA (gDNA) and mtDNA were profiled by specific quantitative PCR. Statistical analyses defined correlations among DNA contents, embryo morphology and maternal age. Different independent tests confirmed the presence of DNA into embryo culture medium and, for the first time, we demonstrate that both gDNA and mtDNA are detectable in the secretome. The amount of DNA is larger in embryos with bad quality cleavage compared with high-grade embryos, suggesting that the DNA profile of culture medium is an objective marker for embryo quality assessment. In particular, DNA profiles are significantly associated with fragmentation feature (total dsDNA: P = 0.0010; mtDNA; P = 0.0247) and advanced maternal age. It is necessary to establish whether DNA profiling of spent embryo culture medium is a robust onsite test that can improve the prediction of blastulation, implantation and/or pregnancy rate. The

Birth of a healthy infant following preimplantation PKHD1 haplotyping for autosomal recessive polycystic kidney disease using multiple displacement amplification

Science.gov (United States)

Janson, Marleen M.; Roesler, Mark R.; Avner, Ellis D.; Strawn, Estil Y.; Bick, David P.

2010-01-01

Purpose To develop a reliable preimplantation genetic diagnosis protocol for couples who both carry a mutant PKHD1 gene wishing to conceive children unaffected with autosomal recessive polycystic kidney disease (ARPKD). Methods Development of a unique protocol for preimplantation genetic testing using whole genome amplification of single blastomeres by multiple displacement amplification (MDA), and haplotype analysis with novel short tandem repeat (STR) markers from the PKHD1 gene and flanking sequences, and a case report of successful utilization of the protocol followed by successful IVF resulting in the birth of an infant unaffected with ARPKD. Results We have developed 20 polymorphic STR markers suitable for linkage analysis of ARPKD. These linked STR markers have enabled unambiguous identification of the PKHD1 haplotypes of embryos produced by at-risk couples. Conclusions We have developed a reliable protocol for preimplantation genetic diagnosis of ARPKD using single-cell MDA products for PKHD1 haplotyping. PMID:20490649

Xenotransplantation of human adipose-derived stem cells in zebrafish embryos.

Directory of Open Access Journals (Sweden)

Jin Li

Full Text Available Zebrafish is a widely used animal model with well-characterized background in developmental biology. The fate of human adipose-derived stem cells (ADSCs after their xenotransplantation into the developing embryos of zebrafish is unknown. Therefore, human ADSCs were firstly isolated, and then transduced with lentiviral vector system carrying a green fluorescent protein (GFP reporter gene, and followed by detection of their cell viability and the expression of cell surface antigens. These GFP-expressing human ADSCs were transplanted into the zebrafish embryos at 3.3-4.3 hour post-fertilization (hpf. Green fluorescent signal, the proliferation and differentiation of human ADSCs in recipient embryos were respectively examined using fluorescent microscopy and immunohistochemical staining. The results indicated that human ADSCs did not change their cell viability and the expression levels of cell surface antigens after GFP transduction. Microscopic examination demonstrated that green fluorescent signals of GFP expressed in the transplanted cells were observed in the embryos and larva fish at post-transplantation. The positive staining of Ki-67 revealed the survival and proliferation of human ADSCs in fish larvae after transplantation. The expression of CD105 was observable in the xenotransplanted ADSCs, but CD31 expression was undetectable. Therefore, our results indicate that human ADSCs xenotransplanted in the zebrafish embryos not only can survive and proliferate at across-species circumstance, but also seem to maintain their undifferentiation status in a short term. This xenograft model of zebrafish embryos may provide a promising and useful technical platform for the investigation of biology and physiology of stem cells in vivo.

Parent-of-origin dependent gene-specific knock down in mouse embryos

International Nuclear Information System (INIS)

Iqbal, Khursheed; Kues, Wilfried A.; Niemann, Heiner

2007-01-01

In mice hemizygous for the Oct4-GFP transgene, the F1 embryos show parent-of-origin dependent expression of the marker gene. F1 embryos with a maternally derived OG2 allele (OG2 mat /-) express GFP in the oocyte and during preimplantation development until the blastocyst stage indicating a maternal and embryonic expression pattern. F1-embryos with a paternally inherited OG2 allele (OG2 pat /-) express GFP from the 4- to 8-cell stage onwards showing only embryonic expression. This allows to study allele specific knock down of GFP expression. RNA interference (RNAi) was highly efficient in embryos with the paternally inherited GFP allele, whereas embryos with the maternally inherited GFP allele showed a delayed and less stringent suppression, indicating that the initial levels of the target transcript and the half life of the protein affect RNAi efficacy. RT-PCR analysis revealed only minimum of GFP mRNA. These results have implications for studies of gene silencing in mammalian embryos

Embryo aggregation does not improve the development of interspecies somatic cell nuclear transfer embryos in the horse.

Science.gov (United States)

Gambini, Andrés; De Stéfano, Adrián; Jarazo, Javier; Buemo, Carla; Karlanian, Florencia; Salamone, Daniel Felipe

2016-09-01

from domestic animals tested in our study, the feline ooplasm might be the most appropriate recipient to partially allow preimplantation embryo development of iSCNT equine embryos. Copyright © 2016 Elsevier Inc. All rights reserved.

Human embryo cloning prohibited in Hong Kong.

Science.gov (United States)

Liu, Athena

2005-12-01

Since the birth of Dolly (the cloned sheep) in 1997, debates have arisen on the ethical and legal questions of cloning-for-biomedical-research (more commonly termed "therapeutic cloning") and of reproductive cloning using human gametes. Hong Kong enacted the Human Reproductive Technology Ordinance (Cap 561) in 2000. Section 15(1)(e) of this Ordinance prohibits the "replacing of the nucleus of a cell of an embryo with a nucleus taken from any other cell," i.e., nucleus substitution. Section 15(1)(f) prohibits the cloning of any embryo. The scope of the latter, therefore, is arguably the widest, prohibiting all cloning techniques such as cell nucleus replacement, embryo splitting, parthenogenesis, and cloning using stem cell lines. Although the Human Reproductive Technology Ordinance is not yet fully operative, this article examines how these prohibitions may adversely impact on basic research and the vision of the Hong Kong scientific community. It concludes that in light of recent scientific developments, it is time to review if the law offers a coherent set of policies in this area.

Igf1r signaling is indispensable for preimplantation development and is activated via a novel function of E-cadherin.

Directory of Open Access Journals (Sweden)

Ivan Bedzhov

Full Text Available Insulin-like growth factor I receptor (Igf1r signaling controls proliferation, differentiation, growth, and cell survival in many tissues; and its deregulated activity is involved in tumorigenesis. Although important during fetal growth and postnatal life, a function for the Igf pathway during preimplantation development has not been described. We show that abrogating Igf1r signaling with specific inhibitors blocks trophectoderm formation and compromises embryo survival during murine blastocyst formation. In normal embryos total Igf1r is present throughout the membrane, whereas the activated form is found exclusively at cell contact sites, colocalizing with E-cadherin. Using genetic domain switching, we show a requirement for E-cadherin to maintain proper activation of Igf1r. Embryos expressing exclusively a cadherin chimera with N-cadherin extracellular and E-cadherin intracellular domains (NcEc fail to form a trophectoderm and cells die by apoptosis. In contrast, homozygous mutant embryos expressing a reverse-structured chimera (EcNc show trophectoderm survival and blastocoel cavitation, indicating a crucial and non-substitutable role of the E-cadherin ectodomain for these processes. Strikingly, blastocyst formation can be rescued in homozygous NcEc embryos by restoring Igf1r signaling, which enhances cell survival. Hence, perturbation of E-cadherin extracellular integrity, independent of its cell-adhesion function, blocked Igf1r signaling and induced cell death in the trophectoderm. Our results reveal an important and yet undiscovered function of Igf1r during preimplantation development mediated by a unique physical interaction between Igf1r and E-cadherin indispensable for proper receptor activation and anti-apoptotic signaling. We provide novel insights into how ligand-dependent Igf1r activity is additionally gated to sense developmental potential in utero and into a bifunctional role of adhesion molecules in contact formation and signaling.

Comparative preimplantation genetic diagnosis policy in Europe and the USA and its implications for reproductive tourism

OpenAIRE

Bayefsky, Michelle J

2017-01-01

Unlike many European nations, the USA has no regulations concerning the use of preimplantation genetic diagnosis (PGD), a technique employed during some fertility treatments to select embryos based on their genes. As such, PGD can and is used for a variety of controversial purposes, including sex selection, selection for children with disabilities such as deafness, and selection for ‘saviour siblings’ who can serve as tissue donors for sick relatives. The lack of regulation, which is due to p...

[Establishment of a novel HLA genotyping method for preimplantation genetic diagnonis using multiple displacement amplification-polymerase chain reaction-sequencing based technique].

Science.gov (United States)

Zhang, Yinfeng; Luo, Haining; Zhang, Yunshan

2015-12-01

To establish a novel HLA genotyping method for preimplantation genetic diagnonis (PGD) using multiple displacement amplification-polymerase chain reaction-sequencing based technique (MDA-PCR-SBT). Peripheral blood samples and 76 1PN, 2PN, 3PN discarded embryos from 9 couples were collected. The alleles of HLA-A, B, DR loci were detected from the MDA product with the PCR-SBT method. The HLA genotypes of the parental peripheral blood samples were analyzed with the same protocol. The genotypes of specific HLA region were evaluated for distinguishing the segregation of haplotypes among the family members, and primary HLA matching was performed between the embryos. The 76 embryos were subjected to MDA and 74 (97.4%) were successfully amplified. For the 34 embryos from the single blastomere group, the amplification rate was 94.1%, and for the 40 embryos in the two blastomeres group, the rate was 100%. The dropout rates for DQ allele and DR allele were 1.3% and 0, respectively. The positive rate for MDA in the single blastomere group was 100%, with the dropout rates for DQ allele and DR allele being 1.5% and 0, respectively. The positive rate of MDA for the two blastomere group was 100%, with the dropout rates for both DQ and DR alleles being 0. The recombination rate of fetal HLA was 20.2% (30/148). Due to the improper classification and abnormal fertilized embryos, the proportion of matched embryos HLA was 20.3% (15/74),which was lower than the theoretical value of 25%. PGD with HLA matching can facilitate creation of a HLA-identical donor (saviour child) for umbilical cord blood or bone marrow stem cells for its affected sibling with a genetic disease. Therefore, preimplantation HLA matching may provide a tool for couples desiring to conceive a potential donor progeny for transplantation for its sibling with a life-threatening disorder.

Preimplantation genetic diagnosis outcomes and meiotic segregation analysis of robertsonian translocation carriers.

Science.gov (United States)

Ko, Duck Sung; Cho, Jae Won; Lee, Hyoung-Song; Kim, Jin Yeong; Kang, Inn Soo; Yang, Kwang Moon; Lim, Chun Kyu

2013-04-01

To investigate the meiotic segregation patterns of cleavage-stage embryos from robertsonian translocation carriers and aneuploidy of chromosome 18 according to meiotic segregation patterns. Retrospective study. Infertility center and laboratory of reproductive biology and infertility. Sixty-two couples with robertsonian translocation carriers. One blastomere was biopsied from embryos and diagnosed with the use of fluorescence in situ hybridization (FISH). Translocation chromosomes were analyzed with the use of locus-specific and subtelomeric FISH probes. Aneuploidy of chromosome 18 was assessed simultaneously with translocation chromosomes. Preimplantation genetic diagnosis (PGD) outcomes, meiotic segregation patterns of robertsonian translocation, and aneuploidy of chromosome 18 depending on meiotic segregation patterns. Two hundred seventy embryos of 332 transferrable embryos were transferred in 113 cycles, and 27 healthy babies were born. The alternate segregation was significantly higher in male carriers than in female carriers (43.9% vs. 29.9%, respectively), and adjacent segregation was higher in female carriers than in male carriers (44.7% vs. 38.7%, respectively). Aneuploidy of chromosome 18 was significantly increased in 3:0-segregated or chaotic embryos. Forty-seven alternate embryos were excluded from embryo replacement owing to aneuploidy of chromosome 18. In carriers of robertsonian translocation, meiotic segregation showed differences between men and women. Frequent meiotic errors caused by premature predivision or nondisjunction and less stringent checkpoint in women might cause such differences between sexes. Aneuploidy of chromosome 18 might be influenced by meiotic segregation of translocation chromosomes. Factors that cause malsegregation, such as 3:0 or chaotic segregation, seem to play a role in aneuploidy of chromosome 18. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

First successful trial of preimplantation genetic diagnosis for pantothenate kinase-associated neurodegeneration.

Science.gov (United States)

Trachoo, Objoon; Satirapod, Chonthicha; Panthan, Bhakbhoom; Sukprasert, Matchuporn; Charoenyingwattana, Angkana; Chantratita, Wasun; Choktanasiri, Wicharn; Hongeng, Suradej

2017-01-01

We aim to present a case of a healthy infant born after intracytoplasmic sperm injection-in vitro fertilization (ICSI-IVF) with a preimplantation genetic diagnosis (PGD) for pantothenate kinase-associated neurodegeneration (PKAN) due to PANK2 mutation. ICSI-IVF was performed on a Thai couple, 34-year-old female and 33-year-old male, with a family history of PKAN in their first child. Following fertilization, each of the embryos were biopsied in the cleavage stage and subsequently processed for whole-genome amplification. Genetic status of the embryos was diagnosed by linkage analysis and direct mutation testing using primer extension-based mini-sequencing. Comprehensive chromosomal aneuploidy screening was performed using a next-generation sequencing-based strategy. Only a single cycle of ICSI-IVF was processed. There were seven embryos from this couple-two were likely affected, three were likely carriers, one was likely unaffected, and one failed in target genome amplification. Aneuploidy screening was performed before making a decision on embryo transfer, and only one unaffected embryo passed the screening. That embryo was transferred in a frozen thawed cycle, and the pregnancy was successful. The diagnosis was confirmed by amniocentesis, which presented with a result consistent with PGD. At 38 weeks of gestational age, a healthy male baby was born. Postnatal genetic confirmation was also consistent with PGD and the prenatal results. At the age of 24 months, the baby presented with normal growth and development lacking any neurological symptoms. We report the first successful trial of PGD for PKAN in a developing country using linkage analysis and mini-sequencing in cleavage stage embryos.

Seminal Fluid Regulates Accumulation of FOXP3(+) Regulatory T Cells in the Preimplantation Mouse Uterus Through Expanding the FOXP3(+) Cell Pool and CCL19-Mediated Recruitment

NARCIS (Netherlands)

Guerin, Leigh R.; Moldenhauer, Lachlan M.; Prins, Jelmer R.; Bromfield, John J.; Hayball, John D.; Robertson, Sarah A.

Regulatory T (Treg) cells facilitate maternal immune tolerance of the semiallogeneic conceptus in early pregnancy, but the origin and regulation of these cells at embryo implantation is unclear. During the preimplantation period, factors in the seminal fluid delivered at coitus cause expansion of a

Correction of β-thalassemia mutant by base editor in human embryos

Directory of Open Access Journals (Sweden)

Puping Liang

2017-09-01

Full Text Available Abstract β-Thalassemia is a global health issue, caused by mutations in the HBB gene. Among these mutations, HBB −28 (A>G mutations is one of the three most common mutations in China and Southeast Asia patients with β-thalassemia. Correcting this mutation in human embryos may prevent the disease being passed onto future generations and cure anemia. Here we report the first study using base editor (BE system to correct disease mutant in human embryos. Firstly, we produced a 293T cell line with an exogenous HBB −28 (A>G mutant fragment for gRNAs and targeting efficiency evaluation. Then we collected primary skin fibroblast cells from a β-thalassemia patient with HBB −28 (A>G homozygous mutation. Data showed that base editor could precisely correct HBB −28 (A>G mutation in the patient’s primary cells. To model homozygous mutation disease embryos, we constructed nuclear transfer embryos by fusing the lymphocyte or skin fibroblast cells with enucleated in vitro matured (IVM oocytes. Notably, the gene correction efficiency was over 23.0% in these embryos by base editor. Although these embryos were still mosaic, the percentage of repaired blastomeres was over 20.0%. In addition, we found that base editor variants, with narrowed deamination window, could promote G-to-A conversion at HBB −28 site precisely in human embryos. Collectively, this study demonstrated the feasibility of curing genetic disease in human somatic cells and embryos by base editor system.

Movement of the external ear in human embryo.

Science.gov (United States)

Kagurasho, Miho; Yamada, Shigehito; Uwabe, Chigako; Kose, Katsumi; Takakuwa, Tetsuya

2012-02-01

External ears, one of the major face components, show an interesting movement during craniofacial morphogenesis in human embryo. The present study was performed to see if movement of the external ears in a human embryo could be explained by differential growth. In all, 171 samples between Carnegie stage (CS) 17 and CS 23 were selected from MR image datasets of human embryos obtained from the Kyoto Collection of Human Embryos. The three-dimensional absolute position of 13 representative anatomical landmarks, including external and internal ears, from MRI data was traced to evaluate the movement between the different stages with identical magnification. Two different sets of reference axes were selected for evaluation and comparison of the movements. When the pituitary gland and the first cervical vertebra were selected as a reference axis, the 13 anatomical landmarks of the face spread out within the same region as the embryo enlarged and changed shape. The external ear did move mainly laterally, but not cranially. The distance between the external and internal ear stayed approximately constant. Three-dimensionally, the external ear located in the caudal ventral parts of the internal ear in CS 17, moved mainly laterally until CS 23. When surface landmarks eyes and mouth were selected as a reference axis, external ears moved from the caudal lateral ventral region to the position between eyes and mouth during development. The results indicate that movement of all anatomical landmarks, including external and internal ears, can be explained by differential growth. Also, when the external ear is recognized as one of the facial landmarks and having a relative position to other landmarks such as the eyes and mouth, the external ears seem to move cranially. © 2012 Kagurasho et al; licensee BioMed Central Ltd.

Dissection of culture media for embryos: the most important and less important components and characteristics.

Science.gov (United States)

Gardner, David K

2008-01-01

Improvements in culture media formulations have led to an increase in the ability to maintain the mammalian embryo in culture throughout the preimplantation and pre-attachment period. Amino acids and specific macromolecules have been identified as being key medium components, whereas temporal dynamics have been recognised as important media characteristics. Furthermore, other laboratory factors that directly impact embryo development and viability have been identified. Such factors include the use of a reduced oxygen tension, an appropriate incubation system and an adequate prescreening of all contact supplies. With rigourous quality systems in place, it is possible to obtain in vivo rates of embryo development in vitro using new media formulations while maintaining high levels of embryo viability. The future of embryo culture will likely be based on novel culture chips capable of providing temporal dynamics while facilitating real-time analysis of embryo physiology.

In vitro and in vivo Development of Cloned Ovine Embryos using in vitro and in vivo Matured Oocytes

DEFF Research Database (Denmark)

Holm, P; Nagashima, H; Sun, F-J

1995-01-01

Cloning of sheep embryos by nucleus transplantation can be achieved by using in vivo matured (oviductal) oocytes and in vivo culture. However, these steps involve cumbersome procedures. Therefore, the effects of in vivo vs. the equivalent in vitro procedures on the pre-implantation development...... matured oocytes were enucleated and fused with inserted blastomeres from donor embryos. In vitro matured oocytes were enucleated and allowed to age prior to blastomere insertion and electrofusion. Fused embryos were cultured for approximately 132 h either in vivo in ligated sheep oviducts or in vitro...

Human embryo-conditioned medium stimulates in vitro endometrial angiogenesis

NARCIS (Netherlands)

Kapiteijn, K.; Koolwijk, P.; Weiden, R.M.F. van der; Nieuw Amerongen, G. van; Plaisier, M.; Hinsbergh, V.W.M. van; Helmerhorst, F.M.

2006-01-01

Objective: Successful implantation and placentation depend on the interaction between the endometrium and the embryo. Angiogenesis is crucial at this time. In this article we investigate the direct influence of the human embryo on in vitro endometrial angiogenesis. Design: In vitro study. Setting:

Saviour Siblings and the Human Fertilisation and Embryology Acts 1990 and 2008 

OpenAIRE

Thorp, Rebecca

2009-01-01

In 2003, the case of R (on the Application of Quintavalle) v Human Fertilisation and Embryology Authority1 dramatically brought into light the Human Fertilisation and Embryology Act 1990 as outdated and inconsistent. Authorisations for saviour sibling treatment appeared futile as cases were decided illogically, leaving some patients having to seek treatment elsewhere. The procedure of pre-implantation genetic diagnosis alongside tissue typing embryos has been a huge breakthrough in treating c...

Is it time for a paradigm shift in understanding embryo selection?

Science.gov (United States)

Gleicher, Norbert; Kushnir, Vitaly A; Barad, David H

2015-01-11

Embryo selection has been an integral feature of in vitro fertilization (IVF) almost since its inception. Since the advent of extended blastocyst stage embryo culture, and especially with increasing popularity of elective single embryo transfer (eSET), the concept of embryo selection has increasingly become a mainstay of routine IVF. We here, however, argue that embryo selection via blastocyst stage embryo transfer (BSET), as currently practiced, at best improves IVF outcomes only for a small minority of patients undergoing IVF cycles. For a large majority BSET is either ineffective or, indeed, may actually be harmful by decreasing IVF pregnancy chances. Overall, only a small minority of patients, thus, benefit from prolonged embryo culture, while BSET, as a tool to enhance IVF outcomes, is increasingly utilized as routine care in IVF for all patients. Since newer methods of embryo selection, like preimplantation genetic screening (PGS) and closed system embryo incubation with time-lapse photography are practically dependent on BSET, these concepts of embryo selection, currently increasingly adopted in mainstream IVF, require reconsideration. They, automatically, transfer the downsides of BSET, including decreases in IVF pregnancy chances in some patients, to these new procedures, and in addition raise serious questions about cost-effectiveness.

Developmental defects and genomic instability after x-irradiation of wild-type and genetically modified mouse pre-implantation and early post-implantation embryos

International Nuclear Information System (INIS)

Jacquet, P

2012-01-01

Results obtained from the end of the 1950s suggested that ionizing radiation could induce foetal malformations in some mouse strains when administered during early pre-implantation stages. Starting in 1989, data obtained in Germany also showed that radiation exposure during that period could lead to a genomic instability in the surviving foetuses. Furthermore, the same group reported that both malformations and genomic instability could be transmitted to the next generation foetuses after exposure of zygotes to relatively high doses of radiation. As such results were of concern for radiation protection, we investigated this in more detail during recent years, using mice with varying genetic backgrounds including mice heterozygous for mutations involved in important cellular processes like DNA repair, cell cycle regulation or apoptosis. The main parameters which were investigated included morphological development, genomic instability and gene expression in the irradiated embryos or their own progeny. The aim of this review is to critically reassess the results obtained in that field in the different laboratories and to try to draw general conclusions on the risks of developmental defects and genomic instability from an exposure of early embryos to moderate doses of ionizing radiation. Altogether and in the range of doses normally used in diagnostic radiology, the risk of induction of embryonic death and of congenital malformation following the irradiation of a newly fertilised egg is certainly very low when compared to the ‘spontaneous’ risks for such effects. Similarly, the risk of radiation induction of a genomic instability under such circumstances seems to be very small. However, this is not a reason to not apply some precaution principles when possible. One way of doing this is to restrict the use of higher dose examinations on all potentially pregnant women to the first ten days of their menstrual cycle when conception is very unlikely to have occurred

The influence of serum substituents on serum-free Vero cell conditioned culture media manufactured from Dulbecco's modified Eagle medium in mouse embryo culture.

Science.gov (United States)

Lee, Jong-Seon; Kim, Ju-Hwan; Seo, Young-Seok; Yang, Jung-Bo; Kim, Yong-Il; Kim, Hye-Jin; Lee, Ki-Hwan

2013-09-01

This study was conducted to examine the influences of supplementation of the serum substituents and available period of serum-free Vero cell conditioned media (SF-VCM) manufactured from Dulbecco's modified Eagle medium cultured with Vero cells for in vitro development of mouse preimplantation embryos. A total of 1,099 two-cell embryos collected from imprinting control region mice were cultured in SF-VCM with 10% and 20% human follicular fluid (hFF), serum substitute supplement (SSS), and serum protein substitute (SPS). Development of embryos was observed every 24 hours. Results between different groups were analyzed by chi-square test, and considered statistically significant when P-value was less than 0.05. The rates of embryonic development cultured in SF-VCM supplemented with serum substituents were significantly higher compare with serum-free group (P media up to 4 weeks did not affect on embryonic development.

RepSox improves viability and regulates gene expression in rhesus monkey-pig interspecies cloned embryos.

Science.gov (United States)

Zhu, Hai-Ying; Jin, Long; Guo, Qing; Luo, Zhao-Bo; Li, Xiao-Chen; Zhang, Yu-Chen; Xing, Xiao-Xu; Xuan, Mei-Fu; Zhang, Guang-Lei; Luo, Qi-Rong; Wang, Jun-Xia; Cui, Cheng-Du; Li, Wen-Xue; Cui, Zheng-Yun; Yin, Xi-Jun; Kang, Jin-Dan

2017-05-01

To investigate the effect of the small molecule, RepSox, on the expression of developmentally important genes and the pre-implantation development of rhesus monkey-pig interspecies somatic cell nuclear transfer (iSCNT) embryos. Rhesus monkey cells expressing the monomeric red fluorescent protein 1 which have a normal (42) chromosome complement, were used as donor cells to generate iSCNT embryos. RepSox increased the expression levels of the pluripotency-related genes, Oct4 and Nanog (p  0.05), this was not significant. RepSox can improve the developmental potential of rhesus monkey-pig iSCNT embryos by regulating the expression of pluripotency-related genes.

Inherited effects from irradiated mouse immature oocytes detected in aggregation embryo chimeras

International Nuclear Information System (INIS)

Straume, T.; Raabe, O.G.; Walsh, K.J.; Wiley, L.M.

1993-01-01

Data obtained using the mouse-preimplantation-embryo-chimera assay are presented that show a transmitted effect following low-dose irradiation of immature oocytes in vivo. Six-week-old female mice were irradiated using 137 Cs-γ-rays (0.05 Gy, 0.15 Gy, and unexposed controls). At 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12 weeks post exposure, the mice were mated and aggregation chimeras made from the 4-cell embryos. Three independent experiments have now been carried out, all showing a significant embryonic cell-proliferation disadvantage of the embryos obtained from the females treated 7 weeks previously, i.e., embryos from oocytes that were immature at the time of radiation exposure. No effect was detected at 1-6 weeks when embryos were obtained from maturing oocytes. Also, the effect was not seen at 8, 9, 10, 11, and 12 weeks post exposure. The implications of these results are discussed in the light of previous studies on mouse oocytes

Complex preimplantation genetic diagnosis for beta-thalassaemia, sideroblastic anaemia, and human leukocyte antigen (HLA)-typing.

Science.gov (United States)

Kakourou, Georgia; Vrettou, Christina; Kattamis, Antonis; Destouni, Aspasia; Poulou, Myrto; Moutafi, Maria; Kokkali, Georgia; Pantos, Konstantinos; Davies, Stephen; Kitsiou-Tzeli, Sophia; Kanavakis, Emmanuel; Traeger-Synodinos, Joanne

2016-01-01

Preimplantation genetic diagnosis (PGD) to select histocompatible siblings to facilitate curative haematopoeitic stem-cell transplantation (HSCT) is now an acceptable option in the absence of an available human leukocyte antigen (HLA) compatible donor. We describe a case where the couple who requested HLA-PGD, were both carriers of two serious haematological diseases, beta-thalassaemia and sideroblastic anaemia. Their daughter, affected with sideroblastic anaemia, was programmed to have HSCT. A multiplex-fluorescent-touchdown-PCR protocol was optimized for the simultaneous amplification of: the two HBB-gene mutated regions (c.118C> T, c.25-26delAA), four short tandem repeats (STRs) in chr11p15.5 linked to the HBB gene, the SLC25A38 gene mutation (c.726C > T), two STRs in chr3p22.1 linked to the SLC25A38 gene, plus eleven informative STRs for HLA-haplotyping (chr6p22.1-21.3). This was followed by real-time nested PCR and high-resolution melting analysis (HRMA) for the detection of HBB and SLC25A38 gene mutations, as well as the analysis of all STRs on an automatic genetic analyzer (sequencer). The couple completed four clinical in vitro fertilization (IVF)/PGD cycles. At least one matched unaffected embryo was identified and transferred in each cycle. A twin pregnancy was established in the fourth PGD cycle and genotyping results at all loci were confirmed by prenatal diagnosis. Two healthy baby girls were delivered at week 38 of pregnancy. The need to exclude two familial disorders for HLA-PGD is rarely encountered. The methodological approach described here is fast, accurate, clinically-validated, and of relatively low cost.

Parliamentary cultures and human embryos: the Dutch and British debates compared

NARCIS (Netherlands)

Kirejczyk, Marta

1999-01-01

Twenty years ago, the technology of in vitro fertilization created a new artefact: the human embryo outside the woman's body. In many countries, political debates developed around this artefact. One of the central questions in these debates is whether it is permissible to use human embryos in

ESHRE PGD Consortium/Embryology Special Interest Group--best practice guidelines for polar body and embryo biopsy for preimplantation genetic diagnosis/screening (PGD/PGS)

DEFF Research Database (Denmark)

Harton, G L; Magli, M C; Lundin, K

2011-01-01

In 2005, the European Society for Human Reproduction and Embryology (ESHRE) Preimplantation Genetic Diagnosis (PGD) Consortium published a set of Guidelines for Best Practice to give information, support and guidance to potential, existing and fledgling PGD programmes (Thornhill AR, De Die...... have seen the introduction of a number of new technologies as well as the evolution of current techniques. Additionally, in light of ESHRE's recent advice on how practice guidelines should be written and formulated, the Consortium believed it was timely to revise and update the PGD guidelines. Rather...

Beneficial effect of two culture systems with small groups of embryos on the development and quality of in vitro-produced bovine embryos.

Science.gov (United States)

Cebrian-Serrano, A; Salvador, I; Silvestre, M A

2014-02-01

Currently, in vitro-produced embryos derived by ovum pick up (OPU) and in vitro fertilization (IVF) technologies represent approximately one-third of the embryos worldwide in cattle. Nevertheless, the culture of small groups of embryos from an individual egg donor is an issue that OPU-IVF laboratories have to face. In this work, we tested whether the development and quality of the preimplantation embryos in vitro cultured in low numbers (five embryos) could be improved by the addition of epidermal growth factor, insulin, transferrin and selenium (EGF-ITS) or by the WOW system. With this aim, immature oocytes recovered from slaughtered heifers were in vitro matured and in vitro fertilized. Presumptive zygotes were then randomly cultured in four culture conditions: one large group (LG) (50 embryos/500 μl medium) and three smaller groups [five embryos/50 μl medium without (control) or with EGF-ITS (EGF-ITS) and five embryos per microwell in the WOW system (WOW)]. Embryos cultured in LG showed a greater ability to develop to blastocyst stage than embryos cultured in smaller groups, while the blastocyst rate of WOW group was significantly higher than in control. The number of cells/blastocyst in LG was higher than control or WOW, whereas the apoptosis rate per blastocyst was lower. On the other hand, the addition of EGF-ITS significantly improved both parameters compared to the control and resulted in similar embryo quality to LG. In conclusion, the WOW system improved embryo development, while the addition of EGF-ITS improved the embryo quality when smaller groups of embryos were cultured. © 2013 Blackwell Verlag GmbH.

Development and validation of concurrent preimplantation genetic diagnosis for single gene disorders and comprehensive chromosomal aneuploidy screening without whole genome amplification.

Science.gov (United States)

Zimmerman, Rebekah S; Jalas, Chaim; Tao, Xin; Fedick, Anastasia M; Kim, Julia G; Pepe, Russell J; Northrop, Lesley E; Scott, Richard T; Treff, Nathan R

2016-02-01

To develop a novel and robust protocol for multifactorial preimplantation genetic testing of trophectoderm biopsies using quantitative polymerase chain reaction (qPCR). Prospective and blinded. Not applicable. Couples indicated for preimplantation genetic diagnosis (PGD). None. Allele dropout (ADO) and failed amplification rate, genotyping consistency, chromosome screening success rate, and clinical outcomes of qPCR-based screening. The ADO frequency on a single cell from a fibroblast cell line was 1.64% (18/1,096). When two or more cells were tested, the ADO frequency dropped to 0.02% (1/4,426). The rate of amplification failure was 1.38% (55/4,000) overall, with 2.5% (20/800) for single cells and 1.09% (35/3,200) for samples that had two or more cells. Among 152 embryos tested in 17 cases by qPCR-based PGD and CCS, 100% were successfully given a diagnosis, with 0% ADO or amplification failure. Genotyping consistency with reference laboratory results was >99%. Another 304 embryos from 43 cases were included in the clinical application of qPCR-based PGD and CCS, for which 99.7% (303/304) of the embryos were given a definitive diagnosis, with only 0.3% (1/304) having an inconclusive result owing to recombination. In patients receiving a transfer with follow-up, the pregnancy rate was 82% (27/33). This study demonstrates that the use of qPCR for PGD testing delivers consistent and more reliable results than existing methods and that single gene disorder PGD can be run concurrently with CCS without the need for additional embryo biopsy or whole genome amplification. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Pregnancy outcomes following 24-chromosome preimplantation genetic diagnosis in couples with balanced reciprocal or Robertsonian translocations.

Science.gov (United States)

Idowu, Dennis; Merrion, Katrina; Wemmer, Nina; Mash, Janine Gessner; Pettersen, Barbara; Kijacic, Dusan; Lathi, Ruth B

2015-04-01

To report live birth rates (LBR) and total aneuploidy rates in a series of patients with balanced translocations who pursued in vitro fertilization (IVF)-preimplantation genetic diagnosis (PGD) cycles. Retrospective cohort analysis. Genetic testing reference laboratory. Seventy-four couples who underwent IVF-PGD due to a parental translocation. IVF cycles and embryo biopsies were performed by referring clinics. Biopsy samples were sent to a single reference lab for PGD for the translocation plus 24-chromosome aneuploidy screening with the use of a single-nucleotide polymorphism (SNP) microarray. LBR per biopsy cycle, aneuploidy rate, embryo transfer (ET) rate, miscarriage rate. The LBR per IVF biopsy cycle was 38%. LBR for patients reaching ET was 52%. Clinical miscarriage rate was 10%. Despite a mean age of 33.8 years and mean of 7 embryos biopsied, there was a 30% chance for no chromosomally normal embryos. Maternal age >35 years, day 3 biopsy, and having fewer than five embryos available for biopsy increased the risk of no ET. IVF-PGD for translocation and aneuploidy screening had good clinical outcomes. Patients carrying a balanced translocation who are considering IVF-PGD should be aware of the high risk of no ET, particularly in women ≥35 years old. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

PREIMPLANTATION GENETIC DIAGNOSIS – 4 YEARS’ EXPERIENCE AT THE DEPARTMENT OF GYNECOLOGY, UNIVERSITY MEDICAL CENTRE LJUBLJANA

Directory of Open Access Journals (Sweden)

Karin Writzl

2018-02-01

Full Text Available Background. Preimplantation genetic diagnosis offers early investigation of embryos in couples with a high risk for offspring affected by a genetic disease. We report indications and results associated with the PGD program conducted at Gynecology Clinic Ljubljana from June 2004 to December 2008. Methods. The retrospective analysis includes sixty cycles performed in 34 couples enrolled in the PGD programe. Embryos were biopsied on the third day and the genetic analysis was performed using the FISH and PCR methods. Embryo transfers were carried out on the fifth day. Results. The main indications were chromosomal abnormalities (67 %, followed by recurrent miscarriages (16 %, autosomal dominant and recessive diseases (9 %, and X-linked diseases (6 %. Sixty cycles were performed and 48 embryo transfer procedures. There were 15 clinical pregnancies resulting in clinical pregnancy rate 25 % per cycle and 37.5 % per embryo transfer. A total of eight unaffected children were born, and two pregnancies are still ongoing. Conclusions. PGD is technically a very challenging procedure. Superior knowledge and communication between geneticists and reproductive medicine scientists is mandatory for successful PGD procedures. PGD has gained a place among the choices offered at Gynecology Clinic Ljubljana to couples at risk of transmission of genetic disease.

Analysis of the expression of putatively imprinted genes in bovine peri-implantation embryos

DEFF Research Database (Denmark)

Tveden-Nyborg, Pernille Yde; Alexopoulos, N.I.; Cooney, M.A.

2008-01-01

The application of assisted reproductive technologies (ART) has been shown to induce changes in the methylation of the embryonic genome, leading to aberrant gene expression, including that of imprinted genes. Aberrant methylation and gene expression has been linked to the large offspring syndrome...... (LOS) in bovine embryos resulting in increased embryonic morbidity and mortality. In the bovine, limited numbers of imprinted genes have been studied and studies have primarily been restricted to pre-implantation stages. This study reports original data on the expression pattern of 8 putatively...... imprinted genes (Ata3, Dlk1, Gnas, Grb10, Magel2, Mest-1, Ndn and Sgce) in bovine peri-implantation embryos. Two embryonic developmental stages were examined, Day 14 and Day 21. The gene expression pattern of single embryos was recorded for in vivo, in vitro produced (IVP) and parthenogenetic embryos...

In vitro and in vivo Development of Cloned Ovine Embryos using in vitro and in vivo Matured Oocytes

DEFF Research Database (Denmark)

Holm, P; Nagashima, H; Sun, F-J

1995-01-01

Cloning of sheep embryos by nucleus transplantation can be achieved by using in vivo matured (oviductal) oocytes and in vivo culture. However, these steps involve cumbersome procedures. Therefore, the effects of in vivo vs. the equivalent in vitro procedures on the pre-implantation development of...

Generating different genetic expression patterns in the early embryo: insights from the mouse model

Czech Academy of Sciences Publication Activity Database

Bruce, Alexander

2013-01-01

Roč. 27, č. 6 (2013), s. 586-592 ISSN 1472-6483 Grant - others:Marie Curie Career Integration Grant(CZ) IDNOVCELFAT2011; Czech Science Foundation(CZ) 13-032955 Institutional support: RVO:60077344 Keywords : cell fate * preimplantation embryo * probabilistic Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.980, year: 2013 http://www.sciencedirect.com/science/article/pii/S1472648313002435

Association of the transcription profile of bovine oocytes and embryos with developmental potential

Czech Academy of Sciences Publication Activity Database

Kaňka, Jiří; Němcová, Lucie; Toralová, Tereza; Vodičková Kepková, Kateřina; Vodička, Petr; Jeseta, M.; Machatková, M.

2012-01-01

Roč. 134, 1-2 (2012), 29-35 ISSN 0378-4320. [Embryo Genomics Meeting /3./. Bonn, 20.08.2012-22.08.2012] R&D Projects: GA ČR GA523/09/1035; GA MZe QI91A018 Institutional support: RVO:67985904 Keywords : oocyte * in vitro maturation * pre-implantation development Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.897, year: 2012

A systematic analysis of the suitability of preimplantation genetic diagnosis for mitochondrial diseases in a heteroplasmic mitochondrial mouse model.

Science.gov (United States)

Neupane, Jitesh; Vandewoestyne, Mado; Heindryckx, Björn; Ghimire, Sabitri; Lu, Yuechao; Qian, Chen; Lierman, Sylvie; Van Coster, Rudy; Gerris, Jan; Deroo, Tom; Deforce, Dieter; De Sutter, Petra

2014-04-01

What is the reliability of preimplantation genetic diagnosis (PGD) based on polar body (PB), blastomere or trophectoderm (TE) analysis in a heteroplasmic mitochondrial mouse model? The reliability of PGD to determine the level of mitochondrial DNA (mtDNA) heteroplasmy is questionable based on either the first or second PB analysis; however, PGD based on blastomere or TE analysis seems more reliable. PGD has been suggested as a technique to determine the level of mtDNA heteroplasmy in oocytes and embryos to avoid the transmission of heritable mtDNA disorders. A strong correlation between first PBs and oocytes and between second PBs and zygotes was reported in mice but is controversial in humans. So far, the levels of mtDNA heteroplasmy in first PBs, second PBs and their corresponding oocytes, zygotes and blastomeres, TE and blastocysts have not been analysed within the same embryo. We explored the suitability of PGD by comparing the level of mtDNA heteroplasmy between first PBs and metaphase II (MII) oocytes (n = 33), between first PBs, second PBs and zygotes (n = 30), and between first PBs, second PBs and their corresponding blastomeres of 2- (n = 10), 4- (n = 10) and 8-cell embryos (n = 11). Levels of mtDNA heteroplasmy in second PBs (n = 20), single blastomeres from 8-cell embryos (n = 20), TE (n = 20) and blastocysts (n = 20) were also compared. Heteroplasmic mice (BALB/cOlaHsd), containing mtDNA mixtures of BALB/cByJ and NZB/OlaHsd, were used in this study. The first PBs were biopsied from in vivo matured MII oocytes. The ooplasm was then subjected to ICSI. After fertilization, second PBs were biopsied and zygotes were cultured to recover individual blastomeres from 2-, 4- and 8-cell embryos. Similarly, second PBs were biopsied from in vivo fertilized zygotes and single blastomeres were biopsied from 8-cell stage embryos. The remaining embryo was cultured until the blastocyst stage to isolate TE cells. Polymerase chain reaction followed by restriction fragment

Whole genome amplification in preimplantation genetic diagnosis*

Science.gov (United States)

Zheng, Ying-ming; Wang, Ning; Li, Lei; Jin, Fan

2011-01-01

Preimplantation genetic diagnosis (PGD) refers to a procedure for genetically analyzing embryos prior to implantation, improving the chance of conception for patients at high risk of transmitting specific inherited disorders. This method has been widely used for a large number of genetic disorders since the first successful application in the early 1990s. Polymerase chain reaction (PCR) and fluorescent in situ hybridization (FISH) are the two main methods in PGD, but there are some inevitable shortcomings limiting the scope of genetic diagnosis. Fortunately, different whole genome amplification (WGA) techniques have been developed to overcome these problems. Sufficient DNA can be amplified and multiple tasks which need abundant DNA can be performed. Moreover, WGA products can be analyzed as a template for multi-loci and multi-gene during the subsequent DNA analysis. In this review, we will focus on the currently available WGA techniques and their applications, as well as the new technical trends from WGA products. PMID:21194180

ROCK and RHO Playlist for Preimplantation Development: Streaming to HIPPO Pathway and Apicobasal Polarity in the First Cell Differentiation.

Science.gov (United States)

Alarcon, Vernadeth B; Marikawa, Yusuke

2018-01-01

In placental mammalian development, the first cell differentiation produces two distinct lineages that emerge according to their position within the embryo: the trophectoderm (TE, placenta precursor) differentiates in the surface, while the inner cell mass (ICM, fetal body precursor) forms inside. Here, we discuss how such position-dependent lineage specifications are regulated by the RHOA subfamily of small GTPases and RHO-associated coiled-coil kinases (ROCK). Recent studies in mouse show that activities of RHO/ROCK are required to promote TE differentiation and to concomitantly suppress ICM formation. RHO/ROCK operate through the HIPPO signaling pathway, whose cell position-specific modulation is central to establishing unique gene expression profiles that confer cell fate. In particular, activities of RHO/ROCK are essential in outside cells to promote nuclear localization of transcriptional co-activators YAP/TAZ, the downstream effectors of HIPPO signaling. Nuclear localization of YAP/TAZ depends on the formation of apicobasal polarity in outside cells, which requires activities of RHO/ROCK. We propose models of how RHO/ROCK regulate lineage specification and lay out challenges for future investigations to deepen our understanding of the roles of RHO/ROCK in preimplantation development. Finally, as RHO/ROCK may be inhibited by certain pharmacological agents, we discuss their potential impact on human preimplantation development in relation to fertility preservation in women.

[BETWEEN USAGE AND POLEMIC, AN ARGUMENT IN FAVOUR OF CLARIFYING THE TERMINOLOGY FOR PREIMPLANTATION GENETIC DIAGNOSIS].

Science.gov (United States)

Côté, Stéphanie; Ravitsky, Vardit; Hamet, Pavel; Bouffard, Chantal

2015-12-01

Over 30 years ago, preimplantation genetic diagnosis (PGD) was developed to help couples at risk of transmitting a serious genetic disease to their offspring. Today, the range of medical and non-medical uses of PGD has expanded considerably and some raise much controversy. This is the case, for example, with In-Vitro Fertilization to select embryos as 'saviour siblings' or to screen for susceptibility and predisposition to late onset diseases or conditions of variable penetrance. The situation is even more problematic in the case of sex selection or selection of traits that are culturally valued or discredited (such as deafness, behavioral traits, or height). The debate surrounding PGD has been employing terms to describe these particular uses that have contributed to a focus on the negative effects, thus preventing a distinction between the abuses and the benefits of this reproductive technology. In this context, this paper proposes a terminological clarification that would allow distinguishing medical and non-medical use and, therefore, the issues relevant to each. A more accurate and less generic nomenclature could prevent a conflation of different levels of ethical, clinical and social issues under the single term 'PGD'. For the vast majority of medical uses, we propose to keep: 'preimplantation genetic diagnosis (PGD)', which emphasizes that it is a genetic diagnosis. For non-medical uses, we suggest: 'preimplantation genetic trait selection (PGTS)'.

The effect of cigarette smoke on fertilization and pre-implantation development: assessment using animal models, clinical data, and stem cells

Directory of Open Access Journals (Sweden)

Prue Talbot

2011-01-01

Full Text Available Numerous studies have repeatedly shown that women who smoke experience problems establishing and maintaining pregnancies, and recent work has further demonstrated that the in utero effects of smoke may not be manifested until months or even years after birth. The purpose of this review is to examine the recent literature dealing with the effects of cigarette smoke on the earliest stages of human prenatal development. Studies in this area have included the use of animal models, patients undergoing in vitro fertilization, and embryonic stem cell models. Events leading to fertilization, such as cumulus expansion, hyperactivation of sperm motility, and oocyte pick-up by the oviduct are all impaired by smoke exposure in animal models. Steps crucial to fertilization such as the acrosome reaction and sperm binding to the zona pellucida are likewise inhibited by cigarette smoke. Preimplantation embryos and stem cells that model embryos show a number of adverse responses to smoke exposure, including poor adhesion to extracellular matrices, diminished survival and proliferation, and increased apoptosis. The current literature demonstrates that the earliest stages of prenatal development are sensitive to smoke exposure and indicates that pregnant women should be advised not to smoke during this time.

Expression of nucleolar-related proteins in porcine preimplantation embryos produced in vivo and in vitro

DEFF Research Database (Denmark)

Bjerregaard, Bolette; Wrenzycki, Christine; Strejcek, Frantisek

2004-01-01

The expression of nucleolar-related proteins was studied as an indirect marker of the ribosomal RNA (rRNA) gene activation in porcine embryos up to the blastocyst stage produced in vivo and in vitro. A group of the in vivo-developed embryos were cultured with alpha-amanitin to block the de novo...... proteins pRb and p130, which are involved in cell-cycle regulation, was assessed by semiquantitative RT-PCR up to the blastocyst stage. Toward the end of third cell cycle, the nuclei in non-alpha-amanitin-treated, in vivo-produced embryos displayed different stages of transformation of the nuclear...... was delayed in porcine embryos produced in vitro compared to the in vivo-derived counterparts with respect to mRNAs encoding PAF53 and UBF. Moreover, differences existed in the mRNA expression patterns of pRb between in vivo- and in vitro-developed embryos. These findings show, to our knowledge for the first...

Human developmental anatomy: microscopic magnetic resonance imaging (μMRI) of four human embryos (from Carnegie Stage 10 to 20).

Science.gov (United States)

Lhuaire, Martin; Martinez, Agathe; Kaplan, Hervé; Nuzillard, Jean-Marc; Renard, Yohann; Tonnelet, Romain; Braun, Marc; Avisse, Claude; Labrousse, Marc

2014-12-01

Technological advances in the field of biological imaging now allow multi-modal studies of human embryo anatomy. The aim of this study was to assess the high magnetic field μMRI feasibility in the study of small human embryos (less than 21mm crown-rump) as a new tool for the study of human descriptive embryology and to determine better sequence characteristics to obtain higher spatial resolution and higher signal/noise ratio. Morphological study of four human embryos belonging to the historical collection of the Department of Anatomy in the Faculty of Medicine of Reims was undertaken by μMRI. These embryos had, successively, crown-rump lengths of 3mm (Carnegie Stage, CS 10), 12mm (CS 16), 17mm (CS 18) and 21mm (CS 20). Acquisition of images was performed using a vertical nuclear magnetic resonance spectrometer, a Bruker Avance III, 500MHz, 11.7T equipped for imaging. All images were acquired using 2D (transverse, sagittal and coronal) and 3D sequences, either T1-weighted or T2-weighted. Spatial resolution between 24 and 70μm/pixel allowed clear visualization of all anatomical structures of the embryos. The study of human embryos μMRI has already been reported in the literature and a few atlases exist for educational purposes. However, to our knowledge, descriptive or morphological studies of human developmental anatomy based on data collected these few μMRI studies of human embryos are rare. This morphological noninvasive imaging method coupled with other techniques already reported seems to offer new perspectives to descriptive studies of human embryology.

Development of the ventral body wall in the human embryo

NARCIS (Netherlands)

Mekonen, Hayelom K.; Hikspoors, Jill P. J. M.; Mommen, Greet; Köhler, S. Eleonore; Lamers, Wouter H.

2015-01-01

Migratory failure of somitic cells is the commonest explanation for ventral body wall defects. However, the embryo increases ~ 25-fold in volume in the period that the ventral body wall forms, so that differential growth may, instead, account for the observed changes in topography. Human embryos

Courts, legislators and human embryo research: lessons from Ireland.

Science.gov (United States)

Binchy, William

2011-01-01

When it comes to the matter of human embryo research law plays a crucial role in its development by helping to set the boundaries of what may be done, the sanctions for acting outside those boundaries and the rights and responsibilities of key parties. Nevertheless, the philosophical challenges raised by human embryo research, even with the best will of all concerned, may prove too great for satisfactory resolution through the legal process. Taking as its focus the position of Ireland, this paper explores the distinctive constitutional approach taken on this issue and addresses the difficulty of translating sound philosophy into judicial decrees and the difficulty of establishing expert commissions to make law reform proposals on matters of profound normative controversy. It concludes that the Irish experience does have useful lessons for those in other countries who are concerned with the legal approach to research on human embryos and points to the desirability of a diversity of normative positions in order to enrich the quality of the analysis so as to encourage more informed debate in society.

Analysis of compaction initiation in human embryos by using time-lapse cinematography.

Science.gov (United States)

Iwata, Kyoko; Yumoto, Keitaro; Sugishima, Minako; Mizoguchi, Chizuru; Kai, Yoshiteru; Iba, Yumiko; Mio, Yasuyuki

2014-04-01

To analyze the initiation of compaction in human embryos in vitro by using time-lapse cinematography (TLC), with the goal of determining the precise timing of compaction and clarifying the morphological changes underlying the compaction process. One hundred and fifteen embryos donated by couples with no further need for embryo-transfer were used in this study. Donated embryos were thawed and processed, and then their morphological behavior during the initiation of compaction was dynamically observed via time-lapse cinematography (TLC) for 5 days. Although the initiation of compaction occurred throughout the period from the 4-cell to 16-cell stage, 99 (86.1 %) embryos initiated compaction at the 8-cell stage or later, with initiation at the 8-cell stage being most frequent (22.6 %). Of these 99 embryos, 49.5 % developed into good-quality blastocysts. In contrast, of the 16 (13.9 %) embryos that initiated compaction prior to the 8-cell stage, only 18.8 % developed into good-quality blastocysts. Embryos that initiated compaction before the 8-cell stage showed significantly higher numbers of multinucleated blastomeres, due to asynchronism in nuclear division at the third mitotic division resulting from cytokinetic failure. The initiation of compaction primarily occurs at the third mitotic division or later in human embryos. Embryos that initiate compaction before the 8-cell stage are usually associated with aberrant embryonic development (i.e., cytokinetic failure accompanied by karyokinesis).

[The human embryo after Dolly: new practices for new times].

Science.gov (United States)

de Miguel Beriain, Iñigo

2008-01-01

The possiblity of cloning human beings introduced a lot of issues in our ethical and legal frameworks. In this paper, we will put the focus into the necessary changes in the concept of embryo that our legal systems will have to implement in order to face the new situation. The description of the embryo as a group of cells able to develop into a human being will be defended here as the best way of doing so.

Pre implanted mouse embryos as model for uranium toxicology studies

International Nuclear Information System (INIS)

Kundt, Miriam S.

2001-01-01

Full text: The search of 'in vitro' toxicology model that can predict toxicology effects 'in vivo' is a permanent challenge. A toxicology experimental model must to fill to certain requirements: to have a predictive character, an appropriate control to facilitate the interpretation of the data among the experimental groups, and to be able to control the independent variables that can interfere or modify the results that we are analyzing. The preimplantation embryos posses many advantages in this respect: they are a simple model that begins with the development of only one cell. The 'in vitro' model reproduces successfully the 'in vivo' situation. Due to the similarity that exists among the embryos of mammals during this period the model is practically valid for other species. The embryo is itself a stem cell, the toxicology effects are early observed in his clonal development and the physical-chemical parameters are easily controllable. The purpose of the exhibition is to explain the properties of the pre implanted embryo model for toxicology studies of uranium and to show our experimental results. The cultivation 'in vitro' of mouse embryos with uranylo nitrate demonstrated that the uranium causes from the 13 μgU/ml delay of development, decrease the number of cells per embryo and hipoploidy in the embryonic blastomere. (author)

Nutrition and maternal metabolic health in relation to oocyte and embryo quality: critical views on what we learned from the dairy cow model.

Science.gov (United States)

Leroy, Jo L M R; Valckx, Sara D M; Jordaens, Lies; De Bie, Jessie; Desmet, Karolien L J; Van Hoeck, Veerle; Britt, Jack H; Marei, Waleed F; Bols, Peter E J

2015-05-01

Although fragmented and sometimes inconsistent, the proof of a vital link between the importance of the physiological status of the mother and her subsequent reproductive success is building up. High-yielding dairy cows are suffering from a substantial decline in fertility outcome over past decades. For many years, this decrease in reproductive output has correctly been considered multifactorial, with factors including farm management, feed ratios, breed and genetics and, last, but not least, ever-rising milk production. Because the problem is complex and requires a multidisciplinary approach, it is hard to formulate straightforward conclusions leading to improvements on the 'work floor'. However, based on remarkable similarities on the preimplantation reproductive side between cattle and humans, there is a growing tendency to consider the dairy cow's negative energy balance and accompanying fat mobilisation as an interesting model to study the impact of maternal metabolic disorders on human fertility and, more specifically, on oocyte and preimplantation embryo quality. Considering the mutual interest of human and animal scientists studying common reproductive problems, this review has several aims. First, we briefly introduce the 'dairy cow case' by describing the state of the art of research into metabolic imbalances and their possible effects on dairy cow reproduction. Second, we try to define relevant in vitro models that can clarify certain mechanisms by which aberrant metabolite levels may influence embryonic health. We report on recent advances in the assessment of embryo metabolism and meantime critically elaborate on advantages and major limitations of in vitro models used so far. Finally, we discuss hurdles to be overcome to successfully translate the scientific data to the field.

Comprehensive genetic assessment of the human embryo: can empiric application of microarray comparative genomic hybridization reduce multiple gestation rate by single fresh blastocyst transfer?

Science.gov (United States)

Sills, Eric Scott; Yang, Zhihong; Walsh, David J; Salem, Shala A

2012-09-01

The unacceptable multiple gestation rate currently associated with in vitro fertilization (IVF) would be substantially alleviated if the routine practice of transferring more than one embryo were reconsidered. While transferring a single embryo is an effective method to reduce the clinical problem of multiple gestation, rigid adherence to this approach has been criticized for negatively impacting clinical pregnancy success in IVF. In general, single embryo transfer is viewed cautiously by IVF patients although greater acceptance would result from a more effective embryo selection method. Selection of one embryo for fresh transfer on the basis of chromosomal normalcy should achieve the dual objective of maintaining satisfactory clinical pregnancy rates and minimizing the multiple gestation problem, because embryo aneuploidy is a major contributing factor in implantation failure and miscarriage in IVF. The initial techniques for preimplantation genetic screening unfortunately lacked sufficient sensitivity and did not yield the expected results in IVF. However, newer molecular genetic methods could be incorporated with standard IVF to bring the goal of single embryo transfer within reach. Aiming to make multiple embryo transfers obsolete and unnecessary, and recognizing that array comparative genomic hybridization (aCGH) will typically require an additional 12 h of laboratory time to complete, we propose adopting aCGH for mainstream use in clinical IVF practice. As aCGH technology continues to develop and becomes increasingly available at lower cost, it may soon be considered unusual for IVF laboratories to select a single embryo for fresh transfer without regard to its chromosomal competency. In this report, we provide a rationale supporting aCGH as the preferred methodology to provide a comprehensive genetic assessment of the single embryo before fresh transfer in IVF. The logistics and cost of integrating aCGH with IVF to enable fresh embryo transfer are also

Is there an ethical difference between preimplantation genetic diagnosis and abortion?

Science.gov (United States)

Cameron, C; Williamson, R

2003-04-01

When a person at risk of having a child with a genetic illness or disease wishes to have an unaffected child, this can involve difficult choices. If the pregnancy is established by sexual intercourse, the fetus can be tested early in pregnancy, and if affected a decision can be made to abort in the hope that a future pregnancy with an unaffected fetus ensures. Alternatively, preimplantation genetic diagnosis (PGD) can be used after in vitro fertilisation (IVF) to select and implant an unaffected embryo that hopefully will proceed to term and produce a healthy baby. We are aware that many individuals at risk regard the latter as ethically more acceptable than the former, and examine whether there is an ethical difference between these options. We conclude that PGD and implantation of an unaffected embryo is a more acceptable choice ethically than prenatal diagnosis (PND) followed by abortion for the following reasons: Choice after PGD is seen as ethically neutral because a positive result ("a healthy pregnancy") balances a negative result ("the destruction of the affected embryo") simultaneously (assuming the pregnancy proceeds to full term and a healthy baby is born). While there is usually the intention to establish a healthy pregnancy after an abortion, this is not simultaneous; A woman sees abortion as a personal physical violation of her integrity, and as the pregnancy proceeds she increasingly identifies with and gives ethical status to the embryo/fetus as it develops in utero and not in the laboratory; Many people see aborting a fetus as "killing", whereas in the case of PGD the spare embryos are "allowed to die". We argue that this difference of opinion gives further weight to our conclusion, but note that this has been addressed and debated at length by others.

Status of the human embryo: Philosophical Foundations from Phenomenology

Directory of Open Access Journals (Sweden)

Maria Emilia de Oliveira Schpallir Silva

2017-10-01

Full Text Available Given the difficulty in demonstrating the moment of ontogenesis in which personalization takes place, we sought to define, from a philosophic point of view, the nature of the human embryo regarding its individuality, using Phenomenology, specifically reflections of philosophers Bourghet and Merleau-Ponty on the embryo. Although the statement of their individuality does not entail ethical content in itself, from the point of view of ethical responsibility, it is an extremely important fact to be considered in the bioethical reflection about the moment of ontogeny from which human life must (ethical duty be protected.

Closure of the vertebral canal in human embryos and fetuses

NARCIS (Netherlands)

Mekonen, Hayelom K.; Hikspoors, Jill P. J. M.; Mommen, Greet; Kruepunga, Nutmethee; Köhler, S. Eleonore; Lamers, Wouter H.

2017-01-01

The vertebral column is the paradigm of the metameric architecture of the vertebrate body. Because the number of somites is a convenient parameter to stage early human embryos, we explored whether the closure of the vertebral canal could be used similarly for staging embryos between 7 and 10weeks of

Embryo splitting

Directory of Open Access Journals (Sweden)

Karl Illmensee

2010-04-01

Full Text Available Mammalian embryo splitting has successfully been established in farm animals. Embryo splitting is safely and efficiently used for assisted reproduction in several livestock species. In the mouse, efficient embryo splitting as well as single blastomere cloning have been developed in this animal system. In nonhuman primates embryo splitting has resulted in several pregnancies. Human embryo splitting has been reported recently. Microsurgical embryo splitting under Institutional Review Board approval has been carried out to determine its efficiency for blastocyst development. Embryo splitting at the 6–8 cell stage provided a much higher developmental efficiency compared to splitting at the 2–5 cell stage. Embryo splitting may be advantageous for providing additional embryos to be cryopreserved and for patients with low response to hormonal stimulation in assisted reproduction programs. Social and ethical issues concerning embryo splitting are included regarding ethics committee guidelines. Prognostic perspectives are presented for human embryo splitting in reproductive medicine.

Human cloning and embryo research: the 2003 John J. Conley Lecture on medical ethics.

Science.gov (United States)

George, Robert P

2004-01-01

The author, a member of the U.S. President's Council on Bioethics, discusses ethical issues raised by human cloning, whether for purposes of bringing babies to birth or for research purposes. He first argues that every cloned human embryo is a new, distinct, and enduring organism, belonging to the species Homo sapiens, and directing its own development toward maturity. He then distinguishes between two types of capacities belonging to individual organisms belonging to this species, an immediately exerciseable capacity and a basic natural capacity that develops over time. He argues that it is the second type of capacity that is the ground for full moral respect, and that this capacity (and its concomitant degree of respect) belongs to cloned human embryos no less than to adult human beings. He then considers and rejects counter-arguments to his position, including the suggestion that the capacity of embryos is equivalent to the capacity of somatic cells, that full human rights are afforded only to human organisms with functioning brains, that the possibility of twinning diminishes the moral status of embryos, that the fact that people do not typically mourn the loss of early embryos implies that they have a diminished moral status, that the fact that early spontaneous abortions occur frequently diminishes the moral status of embryos, and that his arguments depend upon a concept of ensoulment. He concludes that if the moral status of cloned human embryos is equivalent to that of adults, then public policy should be based upon this assumption.

Prevention of Lysosomal Storage Diseases and Derivation of Mutant Stem Cell Lines by Preimplantation Genetic Diagnosis

Science.gov (United States)

Altarescu, Gheona; Beeri, Rachel; Eiges, Rachel; Epsztejn-Litman, Silvina; Eldar-Geva, Talia; Elstein, Deborah; Zimran, Ari; Margalioth, Ehud J.; Levy-Lahad, Ephrat; Renbaum, Paul

2012-01-01

Preimplantation genetic diagnosis (PGD) allows birth of unaffected children for couples at risk for a genetic disorder. We present the strategy and outcome of PGD for four lysosomal storage disorders (LSD): Tay-Sachs disease (TSD), Gaucher disease (GD), Fabry disease (FD), and Hunter syndrome (HS), and subsequent development of stem cell lines. For each disease, we developed a family-specific fluorescent multiplex single-cell PCR protocol that included the familial mutation and informative markers surrounding the mutation. Embryo biopsy and PGD analysis were performed on either oocytes (polar bodies one and two) or on single blastomeres from a six-cell embryo. We treated twenty families carrying mutations in these lysosomal storage disorders, including 3 couples requiring simultaneous analysis for two disorders (TSD/GD, TSD/balanced Robertsonian translocation 45XYder(21;14), and HS/oculocutaneus albinism). These analyses led to an overall pregnancy rate/embryo transfer of 38% and the birth of 20 unaffected children from 17 families. We have found that PGD for lysosomal disorders is a safe and effective method to prevent birth of affected children. In addition, by using mutant embryos for the derivation of stem cell lines, we have successfully established GD and HS hESC lines for use as valuable models in LSD research. PMID:23320174

Review:Whole genome amplification in preimplantation genetic diagnosis

Institute of Scientific and Technical Information of China (English)

Ying-ming ZHENG; Ning WANG; Lei LI; Fan JIN

2011-01-01

Preimplantation genetic diagnosis(PGD)refers to a procedure for genetically analyzing embryos prior to implantation,improving the chance of conception for patients at high risk of transmitting specific inherited disorders.This method has been widely used for a large number of genetic disorders since the first successful application in the early 1990s.Polymerase chain reaction(PCR)and fluorescent in situ hybridization(FISH)are the two main methods in PGD,but there are some inevitable shortcomings limiting the scope of genetic diagnosis.Fortunately,different whole genome amplification(WGA)techniques have been developed to overcome these problems.Sufficient DNA can be amplified and multiple tasks which need abundant DNA can be performed.Moreover,WGA products can be analyzed as a template for multi-loci and multi-gene during the subsequent DNA analysis.In this review,we will focus on the currently available WGA techniques and their applications,as well as the new technical trends from WGA products.

Noninvasive imaging systems for gametes and embryo selection in IVF programs: a review.

Science.gov (United States)

Omidi, Marjan; Faramarzi, Azita; Agharahimi, Azam; Khalili, Mohammad Ali

2017-09-01

Optimizing the efficiency of the in vitro fertilization procedure by improving pregnancy rates and reducing the risks of multiple pregnancies simultaneously are the primary goals of the current assisted reproductive technology program. With the move to single embryo transfers, the need for more cost-effective and noninvasive methods for embryo selection prior to transfer is paramount. These aims require advancement in a more acquire gametes/embryo testing and selection procedures using high-tech devices. Therefore, the aim of the present review is to evaluate the efficacy of noninvasive imaging systems in the current literatures, focusing on the potential clinical application in infertile patients undergoing assisted reproductive technology treatments. In this regards, three advanced imaging systems of motile sperm organelle morphology examination, polarization microscopy and time-lapse monitoring for the best selection of the gametes and preimplantation embryos are introduced in full. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

Co-culture of human embryos with autologous cumulus cell clusters and its beneficial impact of secreted growth factors on preimplantation development as compared to standard embryo culture in assisted reproductive technologies (ART

Directory of Open Access Journals (Sweden)

Alexandros Vithoulkas

2017-12-01

Conclusion(s: The investigated factors, among other substances, may be causally connected to the beneficial effect observed on embryo development. Our findings suggest that co-culture with autologous cumulus cell clusters improves the outcome of embryo culture in IVF programs.

Molecular cytogenetic analysis of human blastocysts andcytotrophoblasts by multi-color FISH and Spectra Imaging analyses

Energy Technology Data Exchange (ETDEWEB)

Weier, Jingly F.; Ferlatte, Christy; Baumgartner, Adolf; Jung,Christine J.; Nguyen, Ha-Nam; Chu, Lisa W.; Pedersen, Roger A.; Fisher,Susan J.; Weier, Heinz-Ulrich G.

2006-02-08

Numerical chromosome aberrations in gametes typically lead to failed fertilization, spontaneous abortion or a chromosomally abnormal fetus. By means of preimplantation genetic diagnosis (PGD), we now can screen human embryos in vitro for aneuploidy before transferring the embryos to the uterus. PGD allows us to select unaffected embryos for transfer and increases the implantation rate in in vitro fertilization programs. Molecular cytogenetic analyses using multi-color fluorescence in situ hybridization (FISH) of blastomeres have become the major tool for preimplantation genetic screening of aneuploidy. However, current FISH technology can test for only a small number of chromosome abnormalities and hitherto failed to increase the pregnancy rates as expected. We are in the process of developing technologies to score all 24 chromosomes in single cells within a 3 day time limit, which we believe is vital to the clinical setting. Also, human placental cytotrophoblasts (CTBs) at the fetal-maternal interface acquire aneuploidies as they differentiate to an invasive phenotype. About 20-50% of invasive CTB cells from uncomplicated pregnancies were found aneuploidy, suggesting that the acquisition of aneuploidy is an important component of normal placentation, perhaps limiting the proliferative and invasive potential of CTBs. Since most invasive CTBs are interphase cells and possess extreme heterogeneity, we applied multi-color FISH and repeated hybridizations to investigate individual CTBs. In summary, this study demonstrates the strength of Spectral Imaging analysis and repeated hybridizations, which provides a basis for full karyotype analysis of single interphase cells.

Preimplantation genetic diagnosis for chromosomal rearrangements with the use of array comparative genomic hybridization at the blastocyst stage.

Science.gov (United States)

Christodoulou, Christodoulos; Dheedene, Annelies; Heindryckx, Björn; van Nieuwerburgh, Filip; Deforce, Dieter; De Sutter, Petra; Menten, Björn; Van den Abbeel, Etienne

2017-01-01

To establish the value of array comparative genomic hybridization (CGH) for preimplantation genetic diagnosis (PGD) in embryos of translocation carriers in combination with vitrification and frozen embryo transfer in nonstimulated cycles. Retrospective data analysis study. Academic centers for reproductive medicine and genetics. Thirty-four couples undergoing PGD for chromosomal rearrangements from October 2013 to December 2015. Trophectoderm biopsy at day 5 or day 6 of embryo development and subsequently whole genome amplification and array CGH were performed. This approach revealed a high occurrence of aneuploidies and structural rearrangements unrelated to the parental rearrangement. Nevertheless, we observed a benefit in pregnancy rates of these couples. We detected chromosomal abnormalities in 133/207 embryos (64.2% of successfully amplified), and 74 showed a normal microarray profile (35.7%). In 48 of the 133 abnormal embryos (36.1%), an unbalanced rearrangement originating from the parental translocation was identified. Interestingly, 34.6% of the abnormal embryos (46/133) harbored chromosome rearrangements that were not directly linked to the parental translocation in question. We also detected a combination of unbalanced parental-derived rearrangements and aneuploidies in 27 of the 133 abnormal embryos (20.3%). The use of trophectoderm biopsy at the blastocyst stage is less detrimental to the survival of the embryo and leads to a more reliable estimate of the genomic content of the embryo than cleavage-stage biopsy. In this small cohort PGD study, we describe the successful implementation of array CGH analysis of blastocysts in patients with a chromosomal rearrangement to identify euploid embryos for transfer. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Addressing the ethical issues raised by synthetic human entities with embryo-like features

NARCIS (Netherlands)

Aach, John; Lunshof, Jeantine; Iyer, Eswar; Church, George M.

2017-01-01

The "14-day rule" for embryo research stipulates that experiments with intact human embryos must not allow them to develop beyond 14 days or the appearance of the primitive streak. However, recent experiments showing that suitably cultured human pluripotent stem cells can self organize and

Clinical applications of MARSALA for preimplantation genetic diagnosis of spinal muscular atrophy.

Science.gov (United States)

Ren, Yixin; Zhi, Xu; Zhu, Xiaohui; Huang, Jin; Lian, Ying; Li, Rong; Jin, Hongyan; Zhang, Yan; Zhang, Wenxin; Nie, Yanli; Wei, Yuan; Liu, Zhaohui; Song, Donghong; Liu, Ping; Qiao, Jie; Yan, Liying

2016-09-20

Conventional PCR methods combined with linkage analysis based on short tandem repeats (STRs) or Karyomapping with single nucleotide polymorphism (SNP) arrays, have been applied to preimplantation genetic diagnosis (PGD) for spinal muscular atrophy (SMA), an autosome recessive disorder. However, it has limitations in SMA diagnosis by Karyomapping, and these methods are unable to distinguish wild-type embryos with carriers effectively. Mutated allele revealed by sequencing with aneuploidy and linkage analyses (MARSALA) is a new method allowing embryo selection by a one-step next-generation sequencing (NGS) procedure, which has been applied in PGD for both autosome dominant and X-linked diseases in our group previously. In this study, we carried out PGD based on MARSALA for two carrier families with SMA affected children. As a result, one of the couples has given birth to a healthy baby free of mutations in SMA-causing gene. It is the first time that MARSALA was applied to PGD for SMA, and we can distinguish the embryos with heterozygous deletion (carriers) from the wild-type (normal) ones accurately through this NGS-based method. In addition, direct mutation detection allows us to identify the affected embryos (homozygous deletion), which can be regarded as probands for linkage analysis, in case that the affected family member is absent. In the future, the NGS-based MARSALA method is expected to be used in PGD for all monogenetic disorders with known pathogenic gene mutation. Copyright © 2016 Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, and Genetics Society of China. Published by Elsevier Ltd. All rights reserved.

Action of uranium on pre implanted mouse embryos

International Nuclear Information System (INIS)

Kundt, Miriam S.

2001-01-01

The cultured preimplantation embryos are normally employed to evaluate the effects of environmental pollutants specially metals. Embryos were obtained from hybrid females CBA x C57 Bl following induction of super ovulation. They were incubated from 1 cell stage during 120 hs. in M16 cultured medium. Three different experiments were carried out: A, B and C using uranyl nitrate UO 2 (NO 3 ) 2 6H 2 O as source of uranium. In experiment 'A' the embryos were cultivated in the same culture dish containing final U concentrations of 13, 26, 52, 104 and 208 μgU/ml. In experiment 'B' embryos in a one cell stage were placed in culture medium with uranyl nitrate with final U concentrations of 26, 52, 104 μgU/ml. After 24 hours those embryos which had reached the two-cell stage were transferred to another culture dish to which fresh solutions of uranyl nitrate were added, maintaining the same concentrations of the previous one. In experiment 'C' the embryos were cultivated containing final U concentrations of 26, 52 and 104 μgU/ml and they were transferred to another culture dish every day to which fresh solutions of uranyl nitrate were added. Different embryos parameters were analyzed: 1) Development grade; 2) Number of cell per embryo and metaphases index; and 3) Embryo ploidy. 1) Embryos were observed each 24 hs. to evaluate development grade: 2, 4 and 8 cell stage, morula, early -expanded- hatched blastocysts and atresic embryos. No significant differences were observed in the proportion of embryos arrested either in the one-cell or in the two cell stages in control culture medium regarding different concentrations of U, in a total of 4388 embryos analyzed. From 2 cell stage, moment that the embryo begins to synthesize its own ARNm, the delay in embryonic development increased dose dependent. On the other hand, the toxicological effects in the same concentration are increase from 'A' treatment to 'C' treatment. Embriotoxicology effects are evidenced by an increment in

Transition from blastomere to trophectoderm biopsy: comparing two preimplantation genetic testing for aneuploidies strategies.

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Coll, Lluc; Parriego, Mònica; Boada, Montserrat; Devesa, Marta; Arroyo, Gemma; Rodríguez, Ignacio; Coroleu, Bonaventura; Vidal, Francesca; Veiga, Anna

2018-05-25

SummaryShortly after the implementation of comprehensive chromosome screening (CCS) techniques for preimplantation genetic testing for aneuploidies (PGT-A), the discussion about the transition from day 3 to blastocyst stage biopsy was initiated. Trophectoderm biopsy with CCS is meant to overcome the limitations of cleavage-stage biopsy and single-cell analysis. The aim of this study was to assess the results obtained in our PGT-A programme after the implementation of this new strategy. Comparisons between the results obtained in 179 PGT-A cycles with day 3 biopsy (D+3) and fresh embryo transfer, and 204 cycles with trophectoderm biopsy and deferred (frozen-thawed) embryo transfer were established. Fewer embryos were biopsied and a higher euploidy rate was observed in the trophectoderm biopsy group. No differences in implantation (50.3% vs. 61.4%) and clinical pregnancy rate per transfer (56.1% vs. 65.3%) were found. Although the mean number of euploid embryos per cycle did not differ between groups (1.5 ± 1.7 vs. 1.7 ± 1.8), the final number of euploid blastocysts available for transfer per cycle was significantly higher in the trophectoderm biopsy group (1.1 ± 1.3 vs. 1.7 ± 1.8). This factor led to an increased cumulative live birth rate in this last group (34.1% vs. 44.6%). Although both strategies can offer good results, trophectoderm biopsy offers a more robust diagnosis and the intervention is less harmful for the embryos so more euploid blastocysts are finally available for transfer and/or vitrification.

Ultrastructural and autoradiographic studies of nucleolar development and rDNA transcription in preimplantation mouse embryos

Energy Technology Data Exchange (ETDEWEB)

Geuskens, M.; Alexandre, H. (Universite Libre de Bruxelles (Belgium). Dep. de Biologie Moleculaire)

1984-06-01

The development of the nucleoli and the sites of rDNA transcription have been studies by high-resolution autoradiography during the cleavage stages of mouse embryos. The appearance of fibrillar centres at the periphery of the fibrillar primary nucleoli has been observed at the 4-cell stage. Several fibrillar centres interconnected by electron-dense fibrillar strands, form a reticulated region around the fibrillar mass at the 6- to 8-cell stage. After a 10 min pulse with (/sup 3/H)uridine, only this peripheral network is labelled. At the late morula and at the blastocyst stage, the fibrillar component (nucleolonema) of the reticulated nucleoli is labelled after 10 min (/sup 3/H)uridine incorporation. When the embryos are reincubated for 2 h in cold medium, the label is localized mainly in the granular component. Fibrillar centres are not labelled. Autoradiograms of in vitro developed embryos pulsed for 2 h with (/sup 3/H)uridine confirm that the central fibrillar core of the nucleoli of 6- to 8-cell embryos is never labelled. Thus, the fibrillar constituent of this core is not homologous to the fibrillar component of the nucleoli of later stage embryos, which is the site of active rDNA transcription. An interpretation of nucleologenesis during early mouse embryogenesis is proposed.

Ultrastructural and autoradiographic studies of nucleolar development and rDNA transcription in preimplantation mouse embryos

International Nuclear Information System (INIS)

Geuskens, M.; Alexandre, H.

1984-01-01

The development of the nucleoli and the sites of rDNA transcription have been studies by high-resolution autoradiography during the cleavage stages of mouse embryos. The appearance of fibrillar centres at the periphery of the fibrillar primary nucleoli has been observed at the 4-cell stage. Several fibrillar centres interconnected by electron-dense fibrillar strands, form a reticulated region around the fibrillar mass at the 6- to 8-cell stage. After a 10 min pulse with ( 3 H)uridine, only this peripheral network is labelled. At the late morula and at the blastocyst stage, the fibrillar component (nucleolonema) of the reticulated nucleoli is labelled after 10 min ( 3 H)uridine incorporation. When the embryos are reincubated for 2 h in cold medium, the label is localized mainly in the granular component. Fibrillar centres are not labelled. Autoradiograms of in vitro developed embryos pulsed for 2 h with ( 3 H)uridine confirm that the central fibrillar core of the nucleoli of 6- to 8-cell embryos is never labelled. Thus, the fibrillar constituent of this core is not homologous to the fibrillar component of the nucleoli of later stage embryos, which is the site of active rDNA transcription. An interpretation of nucleologenesis during early mouse embryogenesis is proposed. (author)

Successful application of preimplantation genetic diagnosis for beta-thalassaemia and sickle cell anaemia in Italy.

Science.gov (United States)

Chamayou, S; Alecci, C; Ragolia, C; Giambona, A; Siciliano, S; Maggio, A; Fichera, M; Guglielmino, A

2002-05-01

In Italy, the autosomal recessive diseases beta-thalassaemia and sickle cell anaemia are so widespread that in some regions they can be defined as 'social diseases'. In this study, nine clinical applications of preimplantation genetic diagnosis (PGD) were performed for beta-thalassaemia and sickle cell anaemia on seven Sicilian couples and carriers of beta-globin gene mutations. The studied mutations were: Cd39, HbS, IVS1 nt1, IVS1 nt6 and IVS1 nt110. ICSI was performed with partner's sperm on 131 out of 147 retrieved oocytes, and this resulted in 72 zygotes; 32 embryos were successfully biopsied on day 3. The biopsied blastomeres were lysed and the beta-globin alleles amplified by nested PCR. The mutation diagnosis was performed by restriction enzyme digestion and reverse dot-blot. The amplification efficacy was 97.2%. The genotype study of non-transferred and surplus embryos showed that the allele drop-out rate was 8.6%. Seventeen embryos were transferred in utero on day 4. All couples received an embryo transfer; of the four pregnancies obtained, three resulted in live births and one miscarried at 11 weeks. Prenatal diagnosis at the 11th week and miscarriage material analysis confirmed the PGD results. These studies represent the first successful application of PGD for beta-thalassaemia and sickle cell anaemia in Italy.

Single-site neural tube closure in human embryos revisited.

Science.gov (United States)

de Bakker, Bernadette S; Driessen, Stan; Boukens, Bastiaan J D; van den Hoff, Maurice J B; Oostra, Roelof-Jan

2017-10-01

Since the multi-site closure theory was first proposed in 1991 as explanation for the preferential localizations of neural tube defects, the closure of the neural tube has been debated. Although the multi-site closure theory is much cited in clinical literature, single-site closure is most apparent in literature concerning embryology. Inspired by Victor Hamburgers (1900-2001) statement that "our real teacher has been and still is the embryo, who is, incidentally, the only teacher who is always right", we decided to critically review both theories of neural tube closure. To verify the theories of closure, we studied serial histological sections of 10 mouse embryos between 8.5 and 9.5 days of gestation and 18 human embryos of the Carnegie collection between Carnegie stage 9 (19-21 days) and 13 (28-32 days). Neural tube closure was histologically defined by the neuroepithelial remodeling of the two adjoining neural fold tips in the midline. We did not observe multiple fusion sites in neither mouse nor human embryos. A meta-analysis of case reports on neural tube defects showed that defects can occur at any level of the neural axis. Our data indicate that the human neural tube fuses at a single site and, therefore, we propose to reinstate the single-site closure theory for neural tube closure. We showed that neural tube defects are not restricted to a specific location, thereby refuting the reasoning underlying the multi-site closure theory. Clin. Anat. 30:988-999, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

[Ethical viewpoints on cryopreservation of human embryos].

Science.gov (United States)

Weiler, R

1991-01-01

In the introduction the author describes how moral judgements are being formed in the pluralistic structures of today's societies. Moral relativism and subjectivism are the wide spread consequences of empirical anthropological theories. In this situation the necessity of an objective and normative moral theory (Christian natural law theory) is being stressed. Neither biology nor medicine can pronounce final judgements on the value of human life. The arguments in favour of cryoconservation (medical progress, parents wish to have children, cost-reduction) are outweighed by those arguments which maintain that man cannot dispose of human life through the manipulation of the progenitive act outside marriage and of the juman act of procreation. There are also the risks and the endangering of the human value of the embryo, up to prolicide which is considered to be permissible in some cases, on these moral grounds the author objects to the cryoconservation of embryos as does the relevant instruction of the papal magisterium of the Roman Catholic Church (Donum vitae 1987). He does not, however, take a final stance on how the subjective decision of the physician is to be judged in the individual case.

Autophagy in human embryonic stem cells

NARCIS (Netherlands)

Tra, Thien; Gong, Lan; Kao, Lin-Pin; Li, Xue-Lei; Grandela, Catarina; Devenish, Rodney J.; Wolvetang, Ernst; Prescott, Mark

2011-01-01

Autophagy (macroautophagy) is a degradative process that involves the sequestration of cytosolic material including organelles into double membrane vesicles termed autophagosomes for delivery to the lysosome. Autophagy is essential for preimplantation development of mouse embryos and cavitation of

The Preimplantation Genetic Diagnosis: Legal Aspects in the Spanish Law

Directory of Open Access Journals (Sweden)

Marina Moya González

2018-03-01

Full Text Available This paper analyses the preimplantation genetic diagnosis (PGD in Spain, and the legal aspects. It exposes the technical characteristics, as well as the ethical and social consequences. It compares the different rules of law about assisted human reproduction techniques in Spain, and those in some European countries.

Embryos, individuals, and persons: an argument against embryo creation and research.

Science.gov (United States)

Tollefsen, C

2001-01-01

One strategy for arguing that it should be legally permissible to create human embryos, or to use spare human embryos, for scientific research purposes involves the claim that such embryos cannot be persons because they are not human individuals while twinning may yet take place. Being a human individual is considered to be by most people a necessary condition for being a human person. I argue first that such an argument against the personhood of embryos must be rationally conclusive if their destruction in public places such as laboratories is to be countenanced. I base this argument on a popular understanding of the role that the notion of privacy plays in abortion laws. I then argue that such arguments against personhood are not rationally conclusive. The claim that the early embryos is not a human individual is not nearly as obvious as some assert.

Paternal and maternal factors in preimplantation embryogenesis: interaction with the biochemical environment.

Science.gov (United States)

Ménézo, Yves J R

2006-05-01

Paternal effect on embryonic development occurs as early as fertilization. Incorrect formation of the spermatozoon due to centrosome defects and abnormal concentrations of any components involved in the activation process lead to failure immediately or in the subsequent cell cycles. Sperm chromosomal abnormalities result in early embryo developmental arrests. Generally poor spermatozoa lead to poor blastocyst formation. Sperm DNA fragmentation may impair even late post-implantation development. The DNA repair capacity of the oocytes is of major importance. Early preimplantation development, i.e. until maternal to zygotic transition, is maternally driven. Maternal mRNAs and proteins are of major importance, as there is an unavoidable turnover of these reserves. Polyadenylation of these mRNAs is precisely controlled, in order to avoid too early or too late transcription and translation of the housekeeping genes. An important set of maternal regulations, such as DNA stability, transcriptional regulation and protection against oxidative stress, are impaired by age. The embryo biochemical endogenous pool is very important and may depend upon the environment, i.e. the culture medium. Paternal, maternal and environmental factors are unavoidable parameters; they become evident when age impairs oocyte quality.

Research progression on preimplantation genetic diagnosis and screening%胚胎植入前遗传学诊断和筛查的研究进展

Institute of Scientific and Technical Information of China (English)

刘茜桐; 田莉; 师娟子

2016-01-01

胚胎植入前遗传学诊断（ PGD）和筛查（ PGS）是近年来发展的植入前遗传学检测（ PGT）方法。 PGD主要适用于父母携带基因突变或染色体平衡易位，通过体外受精，在胚胎移植前检测特定的突变以及非平衡染色体异常是否传递到卵子或胚胎。 PGS是运用相同的检测方法检测胚胎染色体非整倍性，通过移植正常的胚胎从而提高妊娠率。 PGD／PGS相关检测技术发展日新月异，传统FISH技术逐渐被取代，更多的新技术也在研发中。但是，PGD／PGS仍存在费用昂贵，无法检测所有胚胎异常等不足之处。该文综述PGD／PGS相关进展和PGD／PGS所存在的问题。%Preimplantation genetic diagnosis ( PGD) and preimplantation genetic screening ( PGS) are recently developed preimplantation genetic testing ( PGT) .PGD is applied when one or both genetic parents carry a gene mutation or a balanced chromosomal rearrangement and testing is performed to determine whether that specific mutation or an unbalanced chromosomal complement has been transmitted to the oocyte or embryo .PGS uses the same method for detecting embryo chromosomal aneuploidy in order to improve pregnancy rate .With the development of new technology related with PGD /PGS, FISH is gradually being replaced and new methods are under research .However , PGD/PGS is expensive and can not detect all abnormalities of the embryo .This article reviewed the advancement and shortcomings of PGD/PGS.

Novel Approach of Differential Staining to Detect Necrotic Cells in Preimplantation Embryos

Directory of Open Access Journals (Sweden)

Mohammad Hossein Nasr Esfahani

2007-01-01

Full Text Available Background: This novel approach describes a rapid and simple method for identification of necrotic vs. viable cells within a mammalian blastocyst.Materials and Methods: Hatched bovine blastocysts produced in vitro were first incubated for 30 min in pre-equilibrated culture medium containing propidium iodide (PI; 300μg/ml and bisbenzimide (Hoechst: H33342; 5μg/ml fluorescent dyes. Embryos were then freed from residual dyes by thoroughly washing in warm phosphate buffer saline free of calcium and magnesium (PBS-, fixed in 2.5% glutharaldehyde and washed again in PBS- . Stained embryos afterwards were mounted in a drop of glycerol over a microscopic slide. Prepared samples were examined under an epifluorescent microscope using the same excitation wavelength (330-385nm and barrier filter (400nm to distinguish necrosed vs. viable blastomers as being appeared in red and blue, respectively.Results: Obtained results showed that in cells with altered cell membrane such as late apoptotic or necrotic cells, PI and H33342 readily enter through the cytoplasmic barriers and so the chromatin materials are stained by both, but since PI quenches bisbenzimide fluorescence, necrotic blastomeres are seen in red to pinky red, while live cells are seen just as blue.Conclusion: Obtained results clearly indicated that this novel approach can be used as a simple, feasible and precise method for every embryology lab and with all the mammalian blastocysts produced either in vitro or in vivo. The basic assay can be completed in 60 min, and valuable and reliable information can be obtained about the quality of the embryos.

Promoting Cas9 degradation reduces mosaic mutations in non-human primate embryos

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Tu, Zhuchi; Yang, Weili; Yan, Sen; Yin, An; Gao, Jinquan; Liu, Xudong; Zheng, Yinghui; Zheng, Jiezhao; Li, Zhujun; Yang, Su; Li, Shihua; Guo, Xiangyu; Li, Xiao-Jiang

2017-01-01

CRISPR-Cas9 is a powerful new tool for genome editing, but this technique creates mosaic mutations that affect the efficiency and precision of its ability to edit the genome. Reducing mosaic mutations is particularly important for gene therapy and precision genome editing. Although the mechanisms underlying the CRSIPR/Cas9-mediated mosaic mutations remain elusive, the prolonged expression and activity of Cas9 in embryos could contribute to mosaicism in DNA mutations. Here we report that tagging Cas9 with ubiquitin-proteasomal degradation signals can facilitate the degradation of Cas9 in non-human primate embryos. Using embryo-splitting approach, we found that shortening the half-life of Cas9 in fertilized zygotes reduces mosaic mutations and increases its ability to modify genomes in non-human primate embryos. Also, injection of modified Cas9 in one-cell embryos leads to live monkeys with the targeted gene modifications. Our findings suggest that modifying Cas9 activity can be an effective strategy to enhance precision genome editing. PMID:28155910

Effect of embryo culture media on percentage of males at birth.

Science.gov (United States)

Zhu, Jinliang; Zhuang, Xinjie; Chen, Lixue; Liu, Ping; Qiao, Jie

2015-05-01

Does embryo culture medium influence the percentage of males at birth? The percentage of males delivered after ICSI cycles using G5™ medium was statistically significantly higher than after cycles where Global, G5™ PLUS, and Quinn's Advantage Media were used. Male and female embryos have different physiologies during preimplantation development. Manipulating the energy substrate and adding growth factors have a differential impact on the development of male and female embryos. This was a retrospective analysis of the percentage of males at birth, and included 4411 singletons born from fresh embryo transfer cycles between January 2011 and August 2013 at the Center for Reproductive Medicine of Third Hospital Peking University. Only singleton gestations were included. Participants were excluded if preimplantation genetic diagnosis, donor oocytes and donor sperm were used. The database between January 2011 and August 2013 was searched with unique medical record number, all patients were present in the database with only one cycle. Demographics, cycle characteristics and the percentage of male babies in the four culture media groups were compared with analysis of variance or χ(2) tests. Multivariable logistic regression was done to determine the association between the sex at birth and culture media after adjusting for other confounding factors, including parental age, parental BMI, type of infertility, parity, number of embryos transferred, number of early gestational sacs, cycles with testicular sperm aspiration (TESA)/percutaneous epididymal sperm aspiration (PESA)/testicular sperm extraction (TESE), number of oocytes retrieved, cycles with blastocyst transfers, and gestational age within ICSI group. Within the IVF group, the percentage of males at birth for G5™, Global, Quinn's and G5™ PLUS media were comparable (P > 0.05); however, within the ICSI group, the percentage of male babies in cycles using G5™(56.1%) was statistically significantly higher than

Establishment of a Simple and Useful Way for Preimplantation Genetic Diagnosis of Chromosomal Diseases

Institute of Scientific and Technical Information of China (English)

LUO Haining; ZHU Guijin; LIU Qun; CHEN Wen; LI Zhou

2007-01-01

In order to establish a simple and useful way for preimplantation genetic diagnosis (PGD)of chromosomal diseases in general IVF laboratory, the methods that are most commonly used in the embryo biopsy, fixation of blastomere and fluorescence in situ hybridization were compared. The three aspects of PGD were analyzed respectively. There was no significant difference in further development capacity of embryos between mechanical (79.7%) and chemical biopsy group (78.6%)(P＞0.05). In this study, more cells were successfully fixed with the Tween/HCL method (93.8%) than with the methanol/acetic acid method (80.5%, P＜0.05). There was no significant difference in cytoplasm remains between methanol/acetic acid method and Tween/HCL method (P＞0.05). The hybridization efficiency of fluorescence in situ hybridization was 89.5% in successive denaturation method and 90.9% in codenaturation method with the difference being not significant (P＞0.05). In conclusion, the mechanical or chemical method, Tween/HCL fixation method and codenaturation fluorescence in situ hybridization method can constitute a simple and useful way for PGD of chromosomal diseases.

[The Cagliari (Italy) Court authorizes the preimplantation genetic diagnosis].

Science.gov (United States)

Jorqui Azofra, María

2007-01-01

Today, preimplantation genetic diagnosis (PGD) has been greatly accepted within the framework of positive law of many European countries. Nevertheless, in other countries, such as Italy, it is forbidden by law. The ruling of the Civil Court of Cagliari which has authorized its use to a Sardinian couple, has opened, in this way, a small crack to be able to asses possible modifications to the Italian regulation on this matter. This article analyses the ruling of the Civil Court of Cagliari (Italy) from an ethical and legal perspective. The criteria which is used to analyse the legitimacy or illegitimacy of the practice of PGD is analysed. That is, on reasons which could justify or not the transfer of embryos in vitro to the woman. With this objective in mind, the Italian and Spanish normative models which regulates this controversial subject are looked at. As a conclusion, a critical evaluation of the arguments presented is made.

Preimplantation genetic diagnosis

DEFF Research Database (Denmark)

Bay, Bjorn; Ingerslev, Hans Jakob; Lemmen, Josephine Gabriela

2016-01-01

OBJECTIVE: To study whether women conceiving after preimplantation genetic diagnosis (PGD) and their children have greater risks of adverse pregnancy and birth outcomes compared with children conceived spontaneously or after IVF with or without intracytoplasmic sperm injection (ICSI). DESIGN...

Clinical outcomes for couples containing a reciprocal chromosome translocation carrier without preimplantation genetic diagnosis.

Science.gov (United States)

Yin, Biao; Zhu, Yuanchang; Wu, Tonghua; Shen, Shuqiu; Zeng, Yong; Liang, Desheng

2017-03-01

To evaluate the pregnancy outcomes of couples containing a carrier of a reciprocal chromosome translocation (RCT) after assisted reproductive technology without preimplantation genetic diagnosis. A retrospective study was performed using data for couples with an RCT carrier and control couples with a normal karyotype (1:4 ratio) who underwent assisted reproductive technology cycles at a Chinese fertility center in 2010-2011. The embryos were fertilized via in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). Only the first pick-up cycles were used for analysis. Clinical variables were compared. Compared with the control group (n=164), the RCT group (n=41) had a marginally lower clinical pregnancy rate (46.3% [19/41] vs 54.3% [89/164]), implantation rate (21.7% [23/106] vs 26.9% [118/438]), multiple-gestation pregnancy rate (21.1% [4/19] vs 32.6% [29/89]), and delivery rate (36.6% [15/41] vs 47.6% [78/164]), whereas the spontaneous abortion rate was slightly higher (21.1% [4/19] vs 12.4% [11/89]). However, none of these differences were significant. The clinical outcomes for RCT carriers were acceptable after IVF/ICSI without performing preimplantation genetic diagnosis, indicating that this approach might comprise a feasible alternative fertility treatment for RCT carriers. © 2016 International Federation of Gynecology and Obstetrics.

Biomedical research with human embryos: changes in the legislation on assisted reproduction in Spain.

Science.gov (United States)

Vidal Martínez, Jaime

2006-01-01

This study deals with issues of research with human embryos obtained through in vitro fertilization in the context of the Spanish Law. The paper focuses on Act 14/2006 on techniques of human assisted reproduction, which replaces the previous Act from 1988. The author claims that the main goals of Act 14/2006 are, on the one hand, to eliminate the restrictions affecting research with human embryos put in place by Act 45/2003 and, on the other, to pave the way for a future legislation on biomedical research. This paper argues for the need of an effective and adequate juridical protection of human embryos obtained in vitro according to responsibility and precautionary principles.

Lack of WDR36 leads to preimplantation embryonic lethality in mice and delays the formation of small subunit ribosomal RNA in human cells in vitro.

Science.gov (United States)

Gallenberger, Martin; Meinel, Dominik M; Kroeber, Markus; Wegner, Michael; Milkereit, Philipp; Bösl, Michael R; Tamm, Ernst R

2011-02-01

Mutations in WD repeat domain 36 gene (WDR36) play a causative role in some forms of primary open-angle glaucoma, a leading cause of blindness worldwide. WDR36 is characterized by the presence of multiple WD40 repeats and shows homology to Utp21, an essential protein component of the yeast small subunit (SSU) processome required for maturation of 18S rRNA. To clarify the functional role of WDR36 in the mammalian organism, we generated and investigated mutant mice with a targeted deletion of Wdr36. In parallel experiments, we used RNA interference to deplete WDR36 mRNA in mouse embryos and cultured human trabecular meshwork (HTM-N) cells. Deletion of Wdr36 in the mouse caused preimplantation embryonic lethality, and essentially similar effects were observed when WDR36 mRNA was depleted in mouse embryos by RNA interference. Depletion of WDR36 mRNA in HTM-N cells caused apoptotic cell death and upregulation of mRNA for BAX, TP53 and CDKN1A. By immunocytochemistry, staining for WDR36 was observed in the nucleolus of cells, which co-localized with that of nucleolar proteins such as nucleophosmin and PWP2. In addition, recombinant and epitope-tagged WDR36 localized to the nucleolus of HTM-N cells. By northern blot analysis, a substantial decrease in 21S rRNA, the precursor of 18S rRNA, was observed following knockdown of WDR36. In addition, metabolic-labeling experiments consistently showed a delay of 18S rRNA maturation in WDR36-depleted cells. Our results provide evidence that WDR36 is an essential protein in mammalian cells which is involved in the nucleolar processing of SSU 18S rRNA.

[Preimplantation genetic diagnosis and monogenic inherited eye diseases].

Science.gov (United States)

Hlavatá, L; Ďuďáková, Ľ; Trková, M; Soldátová, I; Skalická, P; Kousal, B; Lišková, P

Preimplantation genetic diagnosis (PGD) is an established application of genetic testing in the context of in vitro fertilization. PGD is an alternative method to prenatal diagnosis which aims to prevent the transmission of an inherited disorder to the progeny by implanting only embryos that do not carry genetic predisposition for a particular disease. The aim of this study is to provide an overview of eye disorders for which PGD has been carried out. The European literature search focused on best practices, ethical issues, risks and results of PGD for inherited eye disorders. PGD is performed for a number of ocular disorders; a prerequisite for its application is however, the knowledge of a disease-causing mutation(s). The main advantage of this method is that the couple is not exposed to a decision of whether or not to undergo an abortion. Qualified counselling must be provided prior to the PGD in order to completely understand the risk of disability in any child conceived, consequences of disease manifestation, and advantages as well as limitations of this method. In the group of non-syndromic eye diseases and diseases in which ocular findings dominate, PGD has been performed in European countries for aniridia, choroideremia, congenital fibrosis of extraocular muscles, Leber congenital amaurosis, ocular albinism, retinitis pigmentosa, X-linked retinoschisis, Stargardt disease, blepharophimosis-ptosis-inverse epicanthus syndrome and retinoblastoma. Sexing for X-linked or mitochondrial diseases has been carried out for blue cone monochromatism, choroideremia, familial exudative vitreoretinopathy, Leber hereditary optic neuropathy, macular dystrophy (not further specified), Norrie disease, X-linked congenital stationary night blindness, X-linked retinoschisis and nystagmus (not further specified). In recent years, there has been an increase in potential to use PGD. The spectrum of diseases for this method has widened to include severe inherited eye diseases

Ethical acceptability of research on human-animal chimeric embryos: summary of opinions by the Japanese Expert Panel on Bioethics.

Science.gov (United States)

Mizuno, Hiroshi; Akutsu, Hidenori; Kato, Kazuto

2015-01-01

Human-animal chimeric embryos are embryos obtained by introducing human cells into a non-human animal embryo. It is envisaged that the application of human-animal chimeric embryos may make possible many useful research projects including producing three-dimensional human organs in animals and verification of the pluripotency of human ES cells or iPS cells in vivo. The use of human-animal chimeric embryos, however, raises several ethical and moral concerns. The most fundamental one is that human-animal chimeric embryos possess the potential to develop into organisms containing human-derived tissue, which may lead to infringing upon the identity of the human species, and thus impairing human dignity. The Japanese Expert Panel on Bioethics in the Cabinet Office carefully considered the scientific significance and ethical acceptability of the issue and released its "Opinions regarding the handling of research using human-animal chimeric embryos". The Panel proposed a framework of case-by-case review, and suggested that the following points must be carefully reviewed from the perspective of ethical acceptability: (a) Types of animal embryos and types of animals receiving embryo transfers, particularly in dealing with non-human primates; (b) Types of human cells and organs intended for production, particularly in dealing with human nerve or germ cells; and (c) Extent of the period required for post-transfer studies. The scientific knowledge that can be gained from transfer into an animal uterus and from the production of an individual must be clarified to avoid unnecessary generation of chimeric animals. The time is ripe for the scientific community and governments to start discussing the ethical issues for establishing a global consensus.

Microdrop preparation factors influence culture-media osmolality, which can impair mouse embryo preimplantation development.

Science.gov (United States)

Swain, J E; Cabrera, L; Xu, X; Smith, G D

2012-02-01

Because media osmolality can impact embryo development, the effect of conditions during microdrop preparation on osmolality was examined. Various sizes of microdrops were prepared under different laboratory conditions. Drops were pipetted directly onto a dish and covered by oil (standard method) or pipetted on the dish, overlaid with oil before removing the underlying media and replaced with fresh media (wash-drop method). Drops were made at 23°C or on a heated stage (37°C) and with or without airflow. Osmolality was assessed at 5 min and 24h. The biological impact of osmolality change was demonstrated by culturing 1-cell mouse embryos in media with varying osmolality. Reduced drop volume, increased temperature and standard method were associated with a significant increase in osmolality at both 5 min and 24h (P-values media with elevated osmolality (>310mOsm/kg; P<0.05). Procedures in the IVF laboratory can alter osmolality and impact embryo development. Copyright © 2011 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

The Effects of Progesterone on Oocyte Maturation and Embryo Development

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Saeed Zavareh

2013-01-01

Full Text Available Oocyte maturation and embryo development are controlled by intra-ovarian factors suchas steroid hormones. Progesterone (P4 exists in the follicular fluid that contributes tonormal mammalian ovarian function and has several critical functions during embryodevelopment and implantation, including endometrial receptivity, embryonic survivalduring gestation and transformation of the endometrial stromal cells to decidual cells.It is well known that the physiological effects of P4 during the pre-implantation stages ofsome mammal’s embryos are mediated by P4 receptors and their gene expression is determined.The effects of P4 on oocytes and embryo development have been assessed bysome investigations, with contradictory results. P4, a dominant steroid in follicular fluidat approximately 18 hours after the luteinizing hormone (LH surge may have a criticalrole in maturation of oocytes at the germinal stage. However, it has been shown that differentconcentrations of P4 could not improve in vitro maturation rates of germinal vesicles(GV in cumulus oocyte complexes (COCs and cumulus denuded oocytes (CDOs.Culture media supplemented with P4 significantly improved mouse embryo development.In addition, an in vivo experimental design has shown high blastocyst survival andimplantation rates in P4-treated mice.In this review we explain some of the findings that pertain to the effects of P4 onoocyte maturation and embryo development both in vitro and in vivo.

Establishing the role of pre-implantation genetic diagnosis with human leucocyte antigen typing: what place do "saviour siblings" have in paediatric transplantation?

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Samuel, G N; Strong, K A; Kerridge, I; Jordens, C F C; Ankeny, R A; Shaw, P J

2009-04-01

Not all children in need of a haematopoietic stem cell transplant have a suitable relative or unrelated donor available. Recently, in vitro fertilisation (IVF) with pre-implantation genetic diagnosis (PGD) for human leucocyte antigen (HLA) tissue typing has been used to selectively transfer an IVF embryo in order to produce a child who may provide umbilical cord blood for transplantation to an ill sibling. Such children are sometimes called "saviour siblings". To examine the published clinical and epidemiological evidence relevant to the use of this technology, with the aim of clarifying those situations where IVF and PGD for HLA typing should be discussed with parents of an ill child. A critical analysis of published literature on comparative studies of umbilical cord blood versus other sources of stem cells for transplantation; comparative studies of matched unrelated donor versus matched related donor transplantation; and the likelihood of finding an unrelated stem cell donor. IVF and PGD for HLA typing is only applicable when transplantation is non-urgent and parents are of reproductive age. Discussions regarding this technology may be appropriate where no suitable related or unrelated donor is available for a child requiring a transplant, or where no suitable related donor is available and transplantation is only likely to be entertained with a matched sibling donor. Discussion may also be considered in the management of any child lacking a matched related donor who requires a non-urgent transplant or may require a transplant in the future.

In vitro culture of mouse embryos amniotic fluid ID human

African Journals Online (AJOL)

1989-07-15

Jul 15, 1989 ... Because human amniotic fluid is a physiological, balanced ultrafiltrate, it has been considered as an inexpensive alternative culture medium in. IVF. A study of the development of mouse embryos in human amniotic fluid was undertaken to assess the suitability of this as an optional culture medium in human ...

[How can we nowadays select the best embryo to transfer?].

Science.gov (United States)

Alter, L; Boitrelle, F; Sifer, C

2014-01-01

Multiple pregnancies stand as the most common adverse outcome of assisted reproduction technologies (ART) and the dangers associated with those pregnancies have been reduced by doing elective single embryo transfers (e-SET). Many studies have shown that e-SET is compatible with a continuously high pregnancy rate per embryo transfer. Yet, it still becomes necessary to improve the selection process in order to define the quality of individual embryos - so that the ones we choose for transfer are more likely to implant. First, analysis of embryo morphology has greatly helped in this identification and remains the most relevant criterion for choosing the embryo. The introduction of time-lapse imaging provides new criteria predictive of implantation potential, but the real contribution of this system - including the benefit/cost ratio - seems to be not yet properly established. In this context, extended culture until blastocyst stage is an essential practice but it appears wise to keep it for a population showing a good prognosis. Then, the failure of aneuploid embryos to implant properly led to achieve preimplantation genetic screening (PGS) in order to increase pregnancy and delivery rates after ART. However, PGS by fluorescence in situ hybridization (FISH) at day 3 is a useless process - and may even be harmful. Another solution involves using comparative genomic hybridisation (CGH) and moving to blastocyst biopsy. Finally, it is envisaged that morphology will also be significantly aided by non-invasive analysis of biomarkers in the culture media that give a better reflection of whole-embryo physiology and function. Copyright © 2014. Published by Elsevier SAS.

Toxicity testing of human assisted reproduction devices using the mouse embryo assay.

NARCIS (Netherlands)

Punt-Van der Zalm, J.P.; Hendriks, J.C.M.; Westphal, J.R.; Kremer, J.A.M.; Teerenstra, S.; Wetzels, A.M.M.

2009-01-01

Systems to assess the toxicity of materials used in human assisted reproduction currently lack efficiency and/or sufficient discriminatory power. The development of 1-cell CBA/B6 F1 hybrid mouse embryos to blastocysts, expressed as blastocyst rate (BR), is used to measure toxicity. The embryos were

The moral status of the embryo: an attempt at an analysis with the aid of David Hume's ethics.

Science.gov (United States)

Engel, J B; Hönig, A; Segerer, S; Häusler, S F M; Dietl, J; Djakovic, A

2010-12-01

This article applies the moral sentimentalism founded by David Hume to the moral status of the embryo. It will attempt to explain the paradoxical fact that in Germany abortion is common and socially accepted while preimplantation genetic diagnosis is banned with the aid of an approach based on moral sentimentalism. David Hume established the thesis that the human being is guided by the emotions and not by reason when making moral decisions. Scientific innovations often create a feeling of anxiety. Consequently, the initial moral judgment about it is negative. Due to this habit, the innovation is often accepted after a phase of indifference. This phenomenon has been observed in the case of heart transplantation, as well as for IVF. Consequently, the apparent contradiction in the varying degrees of the embryo's worthiness of protection in the womb and in the Petri dish is due to the simple fact that these are different stages of habituation. Therefore, the ethics of Hume cannot stipulate the embryo's moral status for once and for all; however, they can paradoxically raise the ongoing current debate to a more rational level through the insight that the underlying moral concepts are not based on reason alone. Copyright © 2010 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

The clinical effectiveness of preimplantation genetic diagnosis for aneuploidy in all 24 chromosomes (PGD-A): systematic review.

Science.gov (United States)

Lee, Evelyn; Illingworth, Peter; Wilton, Leeanda; Chambers, Georgina Mary

2015-02-01

Is preimplantation genetic diagnosis for aneuploidy (PGD-A) with analysis of all chromosomes during assisted reproductive technology (ART) clinically and cost effective? The majority of published studies comparing a strategy of PGD-A with morphologically assessed embryos have reported a higher implantation rate per embryo using PGD-A, but insufficient data has been presented to evaluate the clinical and cost-effectiveness of PGD-A in the clinical setting. Aneuploidy is a leading cause of implantation failure, miscarriage and congenital abnormalities in humans, and a significant cause of ART failure. Preclinical evidence of PGD-A indicates that the selection and transfer of euploid embryos during ART should improve clinical outcomes. A systematic review of the literature was performed for full text English language articles using MEDLINE, EMBASE, SCOPUS, Cochrane Library databases, NHS Economic Evaluation Database and EconLit. The Downs and Black scoring checklist was used to assess the quality of studies. Clinical effectiveness was measured in terms of pregnancy, live birth and miscarriage rates. Nineteen articles meeting the inclusion criteria, comprising three RCTs in young and good prognosis patients and 16 observation studies were identified. Five of the observational studies included a control group of patients where embryos were selected based on morphological criteria (matched cohort studies). Of the five studies that included a control group and reported implantation rates, four studies (including two RCTs) demonstrated improved implantation rates in the PGD-A group. Of the eight studies that included a control group, six studies (including two RCTs) reported significantly higher pregnancy rates in the PGD-A group, and in the remaining two studies, equivalent pregnancies rates were reported despite fewer embryos being transferred in the PGD-A group. The three RCTs demonstrated benefit in young and good prognosis patients in terms of clinical pregnancy rates

Local activation of uterine Toll-like receptor 2 and 2/6 decreases embryo implantation and affects uterine receptivity in mice.

Science.gov (United States)

Sanchez-Lopez, Javier Arturo; Caballero, Ignacio; Montazeri, Mehrnaz; Maslehat, Nasim; Elliott, Sarah; Fernandez-Gonzalez, Raul; Calle, Alexandra; Gutierrez-Adan, Alfonso; Fazeli, Alireza

2014-04-01

Embryo implantation is a complex interaction between maternal endometrium and embryonic structures. Failure to implant is highly recurrent and impossible to diagnose. Inflammation and infections in the female reproductive tract are common causes of infertility, embryo loss, and preterm labor. The current work describes how the activation of endometrial Toll-like receptor (TLR) 2 and 2/6 reduces embryo implantation chances. We developed a morphometric index to evaluate the effects of the TLR 2/6 activation along the uterine horn (UH). TLR 2/6 ligation reduced the endometrial myometrial and glandular indexes and increased the luminal index. Furthermore, TLR 2/6 activation increased the proinflammatory cytokines such as interleukin (IL)-1beta and monocyte chemotactic protein (MCP)-1 in UH lavages in the preimplantation day and IL-1 receptor antagonist in the implantation day. The engagement of TLR 2/6 with its ligand in the UH during embryo transfer severely affected the rate of embryonic implantation (45.00% ± 6.49% vs. 16.69% ± 5.01%, P embryo implantation process was verified using an in vitro model of human embryo implantation where trophoblast spheroids failed to adhere to a monolayer of TLR 2- and TLR 2/6-activated endometrial cells. The inhibition of TLR receptors 2 and 6 in the presence of their specific ligands restored the ability of the spheroids to bind to the endometrial cells. In conclusion, the activation of the innate immune system in the uterus at the time of implantation interfered with the endometrial receptivity and reduced the chances of implantation success.

Influence of radiation (Co60) in pre-implant rabbit embryos: effect on mitotic index and embryonic pole malformations

International Nuclear Information System (INIS)

Approbato, M.S.; Moura, K.K.V.O.; Florencio, R.S.; Cunha Junior, C.; Garcia, R.; Faria, R.S.; Benedetti, L.N.; Goulart, F.B.

1995-01-01

We studied the effect of ionizing irradiation on 12 New Zealand rabbits (65 embryos), at three different times: at match time (zero hour), two days after and four days after, with two different irradiation doses: five c Gy and ten c Gy. Six rabbits (36 blastocysts) were used as controls. the matching instant was the zero hour. Exactly six days after (± 60 minutes) the embryos of each rabbit was picked up by flushing the uterus with culture media. the embryos were fixed in methanol for 48 hours, and colored with acid Mayer hematoxylin. The following embryo parameters were studied: mitotic index; embryonic pole malformations. There were no gross abnormalities of embryo pole. The mitotic index were altered both by the time and doses. (author)

Preimplantation genetic screening for all 24 chromosomes by microarray comparative genomic hybridization significantly increases implantation rates and clinical pregnancy rates in patients undergoing in vitro fertilization with poor prognosis

Science.gov (United States)

Majumdar, Gaurav; Majumdar, Abha; Lall, Meena; Verma, Ishwar C.; Upadhyaya, Kailash C.

2016-01-01

CONTEXT: A majority of human embryos produced in vitro are aneuploid, especially in couples undergoing in vitro fertilization (IVF) with poor prognosis. Preimplantation genetic screening (PGS) for all 24 chromosomes has the potential to select the most euploid embryos for transfer in such cases. AIM: To study the efficacy of PGS for all 24 chromosomes by microarray comparative genomic hybridization (array CGH) in Indian couples undergoing IVF cycles with poor prognosis. SETTINGS AND DESIGN: A retrospective, case–control study was undertaken in an institution-based tertiary care IVF center to compare the clinical outcomes of twenty patients, who underwent 21 PGS cycles with poor prognosis, with 128 non-PGS patients in the control group, with the same inclusion criterion as for the PGS group. MATERIALS AND METHODS: Single cells were obtained by laser-assisted embryo biopsy from day 3 embryos and subsequently analyzed by array CGH for all 24 chromosomes. Once the array CGH results were available on the morning of day 5, only chromosomally normal embryos that had progressed to blastocyst stage were transferred. RESULTS: The implantation rate and clinical pregnancy rate (PR) per transfer were found to be significantly higher in the PGS group than in the control group (63.2% vs. 26.2%, P = 0.001 and 73.3% vs. 36.7%, P = 0.006, respectively), while the multiple PRs sharply declined from 31.9% to 9.1% in the PGS group. CONCLUSIONS: In this pilot study, we have shown that PGS by array CGH can improve the clinical outcome in patients undergoing IVF with poor prognosis. PMID:27382234

The Chromosomal Constitution of Embryos Arising from Monopronuclear Oocytes in Programmes of Assisted Reproduction

Directory of Open Access Journals (Sweden)

Bernd Rosenbusch

2014-01-01

Full Text Available The assessment of oocytes showing only one pronucleus during assisted reproduction is associated with uncertainty. A compilation of data on the genetic constitution of different developmental stages shows that affected oocytes are able to develop into haploid, diploid, and mosaic embryos with more or less complex chromosomal compositions. In the majority of cases (~80%, haploidy appears to be caused by gynogenesis, whereas parthenogenesis or androgenesis is less common. Most of the diploid embryos result from a fertilization event involving asynchronous formation of the two pronuclei or pronuclear fusion at a very early stage. Uniparental diploidy may sometimes occur if one pronucleus fails to develop and the other pronucleus already contains a diploid genome or alternatively a haploid genome undergoes endoreduplication. In general, the chance of obtaining a biparental diploid embryo appears higher after conventional in vitro fertilization than after intracytoplasmic sperm injection. If a transfer of embryos obtained from monopronuclear oocytes is envisaged, it should be tried to culture them up to the blastocyst since most haploid embryos are not able to reach this stage. Comprehensive counselling of patients on potential risks is advisable before transfer and a preimplantation genetic diagnosis could be offered if available.

Can Characteristics of Reciprocal Translocations Predict the Chance of Transferable Embryos in PGD Cycles?

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Elsbeth Dul

2014-04-01

Full Text Available Translocation carriers have an increased risk of miscarriage or the birth of a child with congenital anomalies. Preimplantation genetic diagnosis (PGD is performed in translocation carriers to select for balanced embryos and, thus, increase the chance of an ongoing pregnancy. However, a common experience is that reciprocal translocation carriers produce a high percentage of unbalanced embryos, which cannot be transferred. Therefore, the pregnancy rates in PGD in this patient group are low. In a cohort of 85 reciprocal translocation carriers undergoing PGD we have searched for cytogenetic characteristics of the translocations that can predict the percentage of balanced embryos. Using shape algorithms, the most likely segregation mode per translocation was determined. Shape algorithm, breakpoint location, and relative chromosome segment sizes proved not to be independent predictors of the percentage of balanced embryos. The ratio of the relative sizes of the translocated segments of both translocation chromosomes can give some insight into the chance of transferable embryos: Very asymmetrical translocations have a higher risk of unbalanced products (p = 0.048. Counseling of the couples on the pros and cons of all their reproductive options remains very important.

On developing a thesis for Reproductive Endocrinology and Infertility fellowship: a case study of ultra-low (2%) oxygen tension for extended culture of human embryos.

Science.gov (United States)

Kaser, Daniel J

2017-03-01

Fellows in Reproductive Endocrinology and Infertility training are expected to complete 18 months of clinical, basic, or epidemiological research. The goal of this research is not only to provide the basis for the thesis section of the oral board exam but also to spark interest in reproductive medicine research and to provide the next generation of physician-scientists with a foundational experience in research design and implementation. Incoming fellows often have varying degrees of training in research methodology and, likewise, different career goals. Ideally, selection of a thesis topic and mentor should be geared toward defining an "answerable" question and building a practical skill set for future investigation. This contribution to the JARG Young Investigator's Forum revisits the steps of the scientific method through the lens of one recently graduated fellow and his project aimed to test the hypothesis that "sequential oxygen exposure (5% from days 1 to 3, then 2% from days 3 to 5) improves blastocyst yield and quality compared to continuous exposure to 5% oxygen among human preimplantation embryos."

Cryopreservation of human embryos and its contribution to in vitro fertilization success rates

NARCIS (Netherlands)

Wong, Kai Mee; Mastenbroek, Sebastiaan; Repping, Sjoerd

2014-01-01

Cryopreservation of human embryos is now a routine procedure in assisted reproductive technologies laboratories. There is no consensus on the superiority of any protocol, and substantial differences exist among centers in day of embryo cryopreservation, freezing method, selection criteria for which

Effect of follicular diameter, time of first cleavage and H3K4 methylation on embryo production rates of Bos indicus cattle

Directory of Open Access Journals (Sweden)

Paula Alvares Lunardelli

2016-10-01

Full Text Available This study aimed investigate the relationship between epigenetics, follicular diameter and cleavage speed, by evaluating the developmental potential and occurence of H3K4 monomethylation of early-, intermediate- and late-cleaving Bos indicus embryos from in vitro fertilized oocytes originating from follicles up to 2 mm in diameter or between 4 and 8 mm in diameter. Oocytes (n = 699 from small follicles (? 2 mm and 639 oocytes from large follicles (4-8 mm were punched from 1,982 Bos indicus’ slaughterhouse ovaries. After maturation and in vitro fertilization (IVF, the cultured embryos were separated into early (? 28 h post-IVF, intermediate (> 28 h and ? 34 h post-IVF and late (> 34 h and ? 54 h post-IVF cleavage groups. Blastocysts were subjected to an immunofluorescence assessment for H3K4me investigation. The blastocyst rate for large follicles (36.3% was higher than that for small follicles (22.9%, P < 0.05. In addition, blastocyst rates for early and intermediate cleavage groups (45.3% and 33.8%, respectively were higher than that for late cleavage group (13.5%, P < 0.05. The blastocysts from all groups displayed H3K4me staining by immunofluorescence, particularly intense in what seemed to be trophectoderm cells and weak or absent in cells seemingly from the inner cell mass. For the first time for indicus embryos, data from this study demonstrate that higher blastocyst embryo rates are obtained from embryos that cleave within 34 h after fertilization and from those produced from follicles of 4-8 mm in diameter, indicating a greater ability of these embryos to develop to the stage of embryonic preimplantation. This is the first article demonstrating the occurrence of H3K4me in cattle embryos; its presence in all the evaluated blastocysts suggests that this histone modification plays a key role in maintaining embryo viability at preimplantation stage.

Evaluation of PCR-based preimplantation genetic diagnosis applied to monogenic diseases: a collaborative ESHRE PGD consortium study

Science.gov (United States)

Dreesen, Jos; Destouni, Aspasia; Kourlaba, Georgia; Degn, Birte; Mette, Wulf Christensen; Carvalho, Filipa; Moutou, Celine; Sengupta, Sioban; Dhanjal, Seema; Renwick, Pamela; Davies, Steven; Kanavakis, Emmanouel; Harton, Gary; Traeger-Synodinos, Joanne

2014-01-01

Preimplantation genetic diagnosis (PGD) for monogenic disorders currently involves polymerase chain reaction (PCR)-based methods, which must be robust, sensitive and highly accurate, precluding misdiagnosis. Twelve adverse misdiagnoses reported to the ESHRE PGD-Consortium are likely an underestimate. This retrospective study, involving six PGD centres, assessed the validity of PCR-based PGD through reanalysis of untransferred embryos from monogenic-PGD cycles. Data were collected on the genotype concordance at PGD and follow-up from 940 untransferred embryos, including details on the parameters of PGD cycles: category of monogenic disease, embryo morphology, embryo biopsy and genotype assay strategy. To determine the validity of PCR-based PGD, the sensitivity (Se), specificity (Sp) and diagnostic accuracy were calculated. Stratified analyses were also conducted to assess the influence of the parameters above on the validity of PCR-based PGD. The analysis of overall data showed that 93.7% of embryos had been correctly classified at the time of PGD, with Se of 99.2% and Sp of 80.9%. The stratified analyses found that diagnostic accuracy is statistically significantly higher when PGD is performed on two cells versus one cell (P=0.001). Se was significantly higher when multiplex protocols versus singleplex protocols were applied (P=0.005), as well as for PGD applied on cells from good compared with poor morphology embryos (P=0.032). Morphology, however, did not affect diagnostic accuracy. Multiplex PCR-based methods on one cell, are as robust as those on two cells regarding false negative rate, which is the most important criteria for clinical PGD applications. Overall, this study demonstrates the validity, robustness and high diagnostic value of PCR-based PGD. PMID:24301057

Influence of embryo culture medium (G5 and HTF) on pregnancy and perinatal outcome after IVF: a multicenter RCT.

Science.gov (United States)

Kleijkers, Sander H M; Mantikou, Eleni; Slappendel, Els; Consten, Dimitri; van Echten-Arends, Jannie; Wetzels, Alex M; van Wely, Madelon; Smits, Luc J M; van Montfoort, Aafke P A; Repping, Sjoerd; Dumoulin, John C M; Mastenbroek, Sebastiaan

2016-10-01

Does embryo culture medium influence pregnancy and perinatal outcome in IVF? Embryo culture media used in IVF affect treatment efficacy and the birthweight of newborns. A wide variety of culture media for human preimplantation embryos in IVF/ICSI treatments currently exists. It is unknown which medium is best in terms of clinical outcomes. Furthermore, it has been suggested that the culture medium used for the in vitro culture of embryos affects birthweight, but this has never been demonstrated by large randomized trials. We conducted a multicenter, double-blind RCT comparing the use of HTF and G5 embryo culture media in IVF. Between July 2010 and May 2012, 836 couples (419 in the HTF group and 417 in the G5 group) were included. The allocated medium (1:1 allocation) was used in all treatment cycles a couple received within 1 year after randomization, including possible transfers with frozen-thawed embryos. The primary outcome was live birth rate. Couples that were scheduled for an IVF or an ICSI treatment at one of the six participating centers in the Netherlands or their affiliated clinics. The live birth rate was higher, albeit nonsignificantly, in couples assigned to G5 than in couples assigned to HTF (44.1% (184/417) versus 37.9% (159/419); RR: 1.2; 95% confidence interval (CI): 0.99-1.37; P = 0.08). Number of utilizable embryos per cycle (2.8 ± 2.3 versus 2.3 ± 1.8; P culture media on perinatal outcome remains to be determined. Embryo culture media used in IVF affect not only treatment efficacy but also perinatal outcome. This suggests that the millions of human embryos that are cultured in vitro each year are sensitive to their environment. These findings should lead to increased awareness, mechanistic studies and legislative adaptations to protect IVF offspring during the first few days of their existence. This project was partly funded by The NutsOhra foundation (Grant 1203-061) and March of Dimes (Grant 6-FY13-153). The authors declare no conflict of

[Relationship between mitochondrial DNA copy number, membrane potential of human embryo and embryo morphology].

Science.gov (United States)

Zhao, H; Teng, X M; Li, Y F

2017-11-25

Objective: To explore the relationship between the embryo with the different morphological types in the third day and its mitochondrial copy number, the membrane potential. Methods: Totally 117 embryos with poor development after normal fertilization and were not suitable transferred in the fresh cycle and 106 frozen embryos that were discarded voluntarily by infertility patients with in vitro fertilization-embryo transfer after successful pregnancy were selected. According to evaluation of international standard in embryos, all cleavage stage embryos were divided into class Ⅰ frozen embryo group ( n= 64), class Ⅱ frozen embryo group ( n= 42) and class Ⅲ fresh embryonic group (not transplanted embryos; n= 117). Real-time PCR and confocal microscopy methods were used to detect mitochondrial DNA (mtDNA) copy number and the mitochondrial membrane potential of a single embryo. The differences between embryo quality and mtDNA copy number and membrane potential of each group were compared. Results: The copy number of mtDNA and the mitochondrial membrane potential in class Ⅲ fresh embryonic group [(1.7±1.0)×10(5) copy/μl, 1.56±0.32] were significantly lower than those in class Ⅰ frozen embryo group [(3.4±1.7)×10(5) copy/μl, 2.66±0.21] and class Ⅱ frozen embryo group [(2.6±1.2)×10(5) copy/μl, 1.80±0.32; all Pembryo group were significantly higher than those in classⅡ frozen embryo group (both Pembryos of the better quality embryo are higher.

No cytotoxic effects from application of pentoxifylline to spermatozoa on subsequent pre-implantation embryo development in mice

Directory of Open Access Journals (Sweden)

Mohammad Ali Khalili

2017-06-01

Full Text Available The aim was to assess the effect of spermatozoa exposed to PTX on the rates of fertilization and embryo development and apoptotic cells within blastocysts in an animal model. Mice Oocytes were inseminated with spermatozoa exposed to 3.6 mmol PTX for 30 min, or with neat spermatozoa. Then fertilization and embryo development rate, blastocyst formation and quality, as well as total cell number of blastocyst, and DNA fragmentation index (DFI in blastocysts were surveyed in both groups. Fertilization and embryo development rate were similar between the groups. The rates of blastocyst formation did not differ significantly between control and PTX groups (52.4% vs. 51.8%. The average of total cell count in blastocysts and DFI in control and PTX groups were also insignificant (31.08 ± 1.5 vs. 34.14 ± 1.5 and 9.76 ± 5.0 vs. 11.77 ± 5.4. Application of PTX for enhancing sperm motility does not cause a cytotoxic effect on subsequent embryo development and embryo genome integrity.

Cytogenetic and genetic studies of radiation-induced chromosome damage in mouse oocytes. Part 1. Numerical and structural chromosome anomalies in metaphase II oocytes, pre- and post-implantation embryos

International Nuclear Information System (INIS)

Tease, Charles; Fisher, Graham

1996-01-01

The incidences of X-ray induced numerical and structural chromosome anomalies were screened in a range of developmental stages from metaphase II oocytes through to post-implantation embryos. Following 1 Gy of acute X-rays to immediately preovulatory stage oocytes, the rate of hyperploidy (chromosome gain) was found to be elevated over levels in unirradiated controls, at metaphase II, in 1-cell and 3.5 day pre-implantation embryos but not in 8.5 day post-implantation foetuses. In the latter, however, the frequency of mosaicism was significantly increased. A similar response of an increase in mosaicism but not in hyperploidy in 8.5 day post-implantation embryos was also found after irradiation of dictyate stage oocytes with 4 Gy of acute X-rays. Significantly elevated frequencies of structural chromosome anomalies were present in metaphase II oocytes and pre-implantation embryonic stages, but could not be detected in block-stained chromosome preparations from 8.5 day post-implantation foetuses. However, analysis of chromosome preparations after G-banding showed that almost 14% of 14.5 day foetuses carried a chromosome rearrangement after 1 Gy of X-rays to immediately preovulatory stage oocytes. Overall, our data indicate that the presence of radiation-induced chromosome gains are incompatible with embryonic survival but that a proportion of embryos with structural chromosome damage develop past mid-gestation. These latter embryos are therefore potentially capable of contributing to the genetic burden of the next generation

Is the creation of admixed embryos "an offense against human dignity"?

Science.gov (United States)

Jones, David Albert

2010-01-01

The controversy over the creation of admixed human-nonhuman embryos, and specifically of what have been termed "cybrids," involves a range of ethical and political issues. It is not reducible to a single question. This paper focuses on one question raised by that controversy, whether creating admixed human-nonhuman entities is "an offense against human dignity. "In the last decade there has been sustained criticism of the use of the concept of human dignity within bioethics. The concept has been criticized as "vague" and "useless." Nevertheless, the concept continues to be invoked in bioethical discussion and in international instruments. This paper defends a concept of human dignity that is coherent but that is wider than contemporary post-Kantian approaches. "Human dignity" is best regarded as having a set of analogically related meanings, more than one of which is relevant to the field of bioethics. A more subtle understanding of the concept of human dignity can help identify what is ethically problematic in human-nonhuman combinations and so shed light on one aspect of the admixed embryo debate.

Mouse cloning and somatic cell reprogramming using electrofused blastomeres.

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Riaz, Amjad; Zhao, Xiaoyang; Dai, Xiangpeng; Li, Wei; Liu, Lei; Wan, Haifeng; Yu, Yang; Wang, Liu; Zhou, Qi

2011-05-01

Mouse cloning from fertilized eggs can assist development of approaches for the production of "genetically tailored" human embryonic stem (ES) cell lines that are not constrained by the limitations of oocyte availability. However, to date only zygotes have been successfully used as recipients of nuclei from terminally differentiated somatic cell donors leading to ES cell lines. In fertility clinics, embryos of advanced embryonic stages are usually stored for future use, but their ability to support the derivation of ES cell lines via somatic nuclear transfer has not yet been proved. Here, we report that two-cell stage electrofused mouse embryos, arrested in mitosis, can support developmental reprogramming of nuclei from donor cells ranging from blastomeres to somatic cells. Live, full-term cloned pups from embryonic donors, as well as pluripotent ES cell lines from embryonic or somatic donors, were successfully generated from these reconstructed embryos. Advanced stage pre-implantation embryos were unable to develop normally to term after electrofusion and transfer of a somatic cell nucleus, indicating that discarded pre-implantation human embryos could be an important resource for research that minimizes the ethical concerns for human therapeutic cloning. Our approach provides an attractive and practical alternative to therapeutic cloning using donated oocytes for the generation of patient-specific human ES cell lines.

Rethinking In Vitro Embryo Culture: New Developments in Culture Platforms and Potential to Improve Assisted Reproductive Technologies1

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Smith, Gary D.; Takayama, Shuichi; Swain, Jason E.

2011-01-01

ABSTRACT The preponderance of research toward improving embryo development in vitro has focused on manipulation of the chemical soluble environment, including altering basic salt composition, energy substrate concentration, amino acid makeup, and the effect of various growth factors or addition or subtraction of other supplements. In contrast, relatively little work has been done examining the physical requirements of preimplantation embryos and the role culture platforms or devices can play in influencing embryo development within the laboratory. The goal of this review is not to reevaluate the soluble composition of past and current embryo culture media, but rather to consider how other controlled and precise factors such as time, space, mechanical interactions, gradient diffusions, cell movement, and surface interactions might influence embryo development. Novel culture platforms are being developed as a result of interdisciplinary collaborations between biologists and biomedical, material, chemical, and mechanical engineers. These approaches are looking beyond the soluble media composition and examining issues such as media volume and embryo spacing. Furthermore, methods that permit precise and regulated dynamic embryo culture with fluid flow and embryo movement are now available, and novel culture surfaces are being developed and tested. While several factors remain to be investigated to optimize the efficiency of embryo production, manipulation of the embryo culture microenvironment through novel devices and platforms may offer a pathway toward improving embryo development within the laboratory of the future. PMID:21998170

Global gene expression profiling of individual human oocytes and embryos demonstrates heterogeneity in early development.

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Lisa Shaw

Full Text Available Early development in humans is characterised by low and variable embryonic viability, reflected in low fecundity and high rates of miscarriage, relative to other mammals. Data from assisted reproduction programmes provides additional evidence that this is largely mediated at the level of embryonic competence and is highly heterogeneous among embryos. Understanding the basis of this heterogeneity has important implications in a number of areas including: the regulation of early human development, disorders of pregnancy, assisted reproduction programmes, the long term health of children which may be programmed in early development, and the molecular basis of pluripotency in human stem cell populations. We have therefore investigated global gene expression profiles using polyAPCR amplification and microarray technology applied to individual human oocytes and 4-cell and blastocyst stage embryos. In order to explore the basis of any variability in detail, each developmental stage is replicated in triplicate. Our data show that although transcript profiles are highly stage-specific, within each stage they are relatively variable. We describe expression of a number of gene families and pathways including apoptosis, cell cycle and amino acid metabolism, which are variably expressed and may be reflective of embryonic developmental competence. Overall, our data suggest that heterogeneity in human embryo developmental competence is reflected in global transcript profiles, and that the vast majority of existing human embryo gene expression data based on pooled oocytes and embryos need to be reinterpreted.

Ultrastructural dynamics of human reproduction, from ovulation to fertilization and early embryo development.

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Familiari, Giuseppe; Heyn, Rosemarie; Relucenti, Michela; Nottola, Stefania A; Sathananthan, A Henry

2006-01-01

This study describes the updated, fine structure of human gametes, the human fertilization process, and human embryos, mainly derived from assisted reproductive technology (ART). As clearly shown, the ultrastructure of human reproduction is a peculiar multistep process, which differs in part from that of other mammalian models, having some unique features. Particular attention has been devoted to the (1) sperm ultrastructure, likely "Tygerberg (Kruger) strict morphology criteria"; (2) mature oocyte, in which the MII spindle is barrel shaped, anastral, and lacking centrioles; (3) three-dimensional microarchitecture of the zona pellucida with its unique supramolecular filamentous organization; (4) sperm-egg interactions with the peculiarity of the sperm centrosome that activates the egg and organizes the sperm aster and mitotic spindles of the embryo; and (5) presence of viable cumulus cells whose metabolic activity is closely related to egg and embryo behavior in in vitro as well as in vivo conditions, in a sort of extraovarian "microfollicular unit." Even if the ultrastructural morphodynamic features of human fertilization are well understood, our knowledge about in vivo fertilization is still very limited and the complex sequence of in vivo biological steps involved in human reproduction is only partially reproduced in current ART procedures.

Transient expression and activity of human DNA polymerase iota in loach embryos.

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Makarova, Irina V; Kazakov, Andrey A; Makarova, Alena V; Khaidarova, Nella V; Kozikova, Larisa V; Nenasheva, Valentina V; Gening, Leonid V; Tarantul, Vyacheslav Z; Andreeva, Ludmila E

2012-02-01

Human DNA polymerase iota (Pol ι) is a Y-family DNA polymerase with unusual biochemical properties and not fully understood functions. Pol ι preferentially incorporates dGTP opposite template thymine. This property can be used to monitor Pol ι activity in the presence of other DNA polymerases, e.g. in cell extracts of tissues and tumors. We have now confirmed the specificity and sensitivity of the method of Pol ι activity detection in cell extracts using an animal model of loach Misgurnus fossilis embryos transiently expressing human Pol ι. The overexpression of Pol ι was shown to be accompanied by an increase in abnormalities in development and the frequency of pycnotic nuclei in fish embryos. Further analysis of fish embryos with constitutive or regulated Pol ι expression may provide insights into Pol ι functions in vertebrate animals.

Graphic and movie illustrations of human prenatal development and their application to embryological education based on the human embryo specimens in the Kyoto collection.

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Yamada, Shigehito; Uwabe, Chigako; Nakatsu-Komatsu, Tomoko; Minekura, Yutaka; Iwakura, Masaji; Motoki, Tamaki; Nishimiya, Kazuhiko; Iiyama, Masaaki; Kakusho, Koh; Minoh, Michihiko; Mizuta, Shinobu; Matsuda, Tetsuya; Matsuda, Yoshimasa; Haishi, Tomoyuki; Kose, Katsumi; Fujii, Shingo; Shiota, Kohei

2006-02-01

Morphogenesis in the developing embryo takes place in three dimensions, and in addition, the dimension of time is another important factor in development. Therefore, the presentation of sequential morphological changes occurring in the embryo (4D visualization) is essential for understanding the complex morphogenetic events and the underlying mechanisms. Until recently, 3D visualization of embryonic structures was possible only by reconstruction from serial histological sections, which was tedious and time-consuming. During the past two decades, 3D imaging techniques have made significant advances thanks to the progress in imaging and computer technologies, computer graphics, and other related techniques. Such novel tools have enabled precise visualization of the 3D topology of embryonic structures and to demonstrate spatiotemporal 4D sequences of organogenesis. Here, we describe a project in which staged human embryos are imaged by the magnetic resonance (MR) microscope, and 3D images of embryos and their organs at each developmental stage were reconstructed based on the MR data, with the aid of computer graphics techniques. On the basis of the 3D models of staged human embryos, we constructed a data set of 3D images of human embryos and made movies to illustrate the sequential process of human morphogenesis. Furthermore, a computer-based self-learning program of human embryology is being developed for educational purposes, using the photographs, histological sections, MR images, and 3D models of staged human embryos. Copyright 2005 Wiley-Liss, Inc.

The first successful live birth following preimplantation genetic diagnosis using PCR for type 1 citrullinemia

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Cho, Jae-Hyun; Lee, Kyung-Hee; Jeon, Il-Kyung; Kim, Jae-Min; Kang, Byung-Moon

2014-01-01

Type 1 citrullinemia (CTLN1) is an autosomal recessive inherited metabolic disorder caused by anargininosuccinicnate synthetase deficiency. The patient was a 38-year-old Korean woman who is a carrier for CTLN1 and her first baby was diagnosed with CTLN1. Preimplantation genetic diagnosis (PGD) for CTLN1 in day 3 embryos using polymerase chain reaction was performed for live birth of healthy baby who is no affected with CTLN1. One unaffected blastocyst was transferred. This resulted in a clinical pregnancy and the live birth of healthy male twin. They were confirmed to be unaffected with CTNL1 by post natal diagnosis. This is the first case report of the use of PGD for CTNL1. PMID:24883299

Development of the epaxial muscles in the human embryo

NARCIS (Netherlands)

Mekonen, Hayelom K.; Hikspoors, Jill P. J. M.; Mommen, Greet; Eleonore KÖhler, S.; Lamers, Wouter H.

2016-01-01

Although the intrinsic muscles of the back are defined by their embryological origin and innervation pattern, no detailed study on their development is available. Human embryos (5-10 weeks development) were studied, using Amira3D® reconstruction and Cinema4D® remodeling software for visualization.

Importance of the pluripotency factor LIN28 in the mammalian nucleolus during early embryonic development.

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Vogt, Edgar J; Meglicki, Maciej; Hartung, Kristina Ilka; Borsuk, Ewa; Behr, Rüdiger

2012-12-01

The maternal nucleolus is required for proper activation of the embryonic genome (EGA) and early embryonic development. Nucleologenesis is characterized by the transformation of a nucleolar precursor body (NPB) to a mature nucleolus during preimplantation development. However, the function of NPBs and the involved molecular factors are unknown. We uncover a novel role for the pluripotency factor LIN28, the biological significance of which was previously demonstrated in the reprogramming of human somatic cells to induced pluripotent stem (iPS) cells. Here, we show that LIN28 accumulates at the NPB and the mature nucleolus in mouse preimplantation embryos and embryonic stem cells (ESCs), where it colocalizes with the nucleolar marker B23 (nucleophosmin 1). LIN28 has nucleolar localization in non-human primate (NHP) preimplantation embryos, but is cytoplasmic in NHP ESCs. Lin28 transcripts show a striking decline before mouse EGA, whereas LIN28 protein localizes to NPBs at the time of EGA. Following knockdown with a Lin28 morpholino, the majority of embryos arrest between the 2- and 4-cell stages and never develop to morula or blastocyst. Lin28 morpholino-injected embryos arrested at the 2-cell stage were not enriched with nucleophosmin at presumptive NPB sites, indicating that functional NPBs were not assembled. Based on these results, we propose that LIN28 is an essential factor of nucleologenesis during early embryonic development.

Successful preimplantation genetic diagnosis by targeted next-generation sequencing on an ion torrent personal genome machine platform.

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Hao, Yan; Chen, Dawei; Zhang, Zhiguo; Zhou, Ping; Cao, Yunxia; Wei, Zhaolian; Xu, Xiaofeng; Chen, Beili; Zou, Weiwei; Lv, Mingrong; Ji, Dongmei; He, Xiaojin

2018-04-01

Hearing loss may place a heavy burden on the patient and patient's family. Given the high incidence of hearing loss among newborns and the huge cost of treatment and care (including cochlear implantation), prenatal diagnosis is strongly recommended. Termination of the fetus may be considered as an extreme outcome to the discovery of a potential deaf fetus, and therefore preimplantation genetic diagnosis has become an important option for avoiding the birth of affected children without facing the risk of abortion following prenatal diagnosis. In one case, a couple had a 7-year-old daughter affected by non-syndromic sensorineural hearing loss. The affected fetus carried a causative compound heterozygous mutation c.919-2 A>G (IVS7-2 A>G) and c.1707+5 G>A (IVS15+5 G>A) of the solute carrier family 26 member 4 gene inherited from maternal and paternal sides, respectively. The present study applied multiple displacement amplification for whole genome amplification of biopsied trophectoderm cells and next-generation sequencing (NGS)-based single nucleotide polymorphism haplotyping on an Ion Torrent Personal Genome Machine. One unaffected embryo was transferred in a frozen-thawed embryo transfer cycle and the patient was impregnated. To conclude, to the best of our knowledge, this may be the first report of NGS-based preimplantation genetic diagnosis (PGD) for non-syndromic hearing loss caused by a compound heterozygous mutation using an Ion Torrent Personal Genome Machine. NGS provides unprecedented high-throughput, highly parallel and base-pair resolution data for genetic analysis. The method meets the requirements of medium-sized diagnostics laboratories. With decreased costs compared with previous techniques (such as Sanger sequencing), this technique may have potential widespread clinical application in PGD of other types of monogenic disease.

Blastocyst Morphology Holds Clues Concerning The Chromosomal Status of The Embryo

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Rita de Cassia Savio Figueira

2015-07-01

Full Text Available Background: Embryo morphology has been proposed as an alternative marker of chromosomal status. The objective of this retrospective cohort study was to investigate the association between the chromosomal status on day 3 of embryo development and blastocyst morphology. Materials and Methods: A total of 596 embryos obtained from 106 cycles of intracytoplasmic sperm injection (ICSI followed by preimplantation genetic aneuploidy screening (PGS were included in this retrospective study. We evaluated the relationship between blastocyst morphological features and embryonic chromosomal alteration. Results: Of the 564 embryos with fluorescent in situ hybridization (FISH results, 200 reached the blastocyst stage on day 5 of development. There was a significantly higher proportion of euploid embryos in those that achieved the blastocyst stage (59.0% compared to embryos that did not develop to blastocysts (41.2% on day 5 (P<0.001. Regarding blastocyst morphology, we observed that all embryos that had an abnormal inner cell mass (ICM were aneuploid. Embryos with morphologically normal ICM had a significantly higher euploidy rate (62.1%, P<0.001. As regards to the trophectoderm (TE morphology, an increased rate of euploidy was observed in embryos that had normal TE (65.8% compared to embryos with abnormal TE (37.5%, P<0.001. Finally, we observed a two-fold increase in the euploidy rate in high-quality blastocysts with both high-quality ICM and TE (70.4% compared to that found in low-quality blastocysts (31.0%, P<0.001. Conclusion: Chromosomal abnormalities do not impair embryo development as aneuploidy is frequently observed in embryos that reach the blastocyst stage. A high-quality blastocyst does not represent euploidy of chromosomes 13, 14, 15, 16, 18, 21, 22, X and Y. However, aneuploidy is associated with abnormalities in the ICM morphology. Further studies are necessary to confirm whether or not the transfer of blastocysts with low-quality ICM should be

Mouse immature oocytes irradiated in vivo at 14-days of age and evaluated for transmitted effects using the aggregation embryo chimera assay

International Nuclear Information System (INIS)

Straume, T.; Raabe, O.G.; Walsh, K.J.; Wiley, L.M.

1996-01-01

A previous study using the mouse-preimplantation-embryo-chimera assay demonstrated a reproducible transmitted effect (proliferation disadvantage observed in early embryos) from females irradiated as 49-day-old adults using 0.15 Gy of gamma rays and then mated seven weeks later, i.e., embryos were from oocytes that were immature at time of irradiation. Because mouse immature oocytes are known to be much more radiosensitive to cell killing in juveniles than in adults, a follow-on study was performed here using 14-day-old juvenile mice. In contrast to adults, the exposure of juveniles to 0.15 Gy of gamma rays did not result in a detectable transmitted proliferation disadvantage when animals were mated 7 or 12 weeks later. This observation is discussed in light of previous studies on mouse immature oocytes and embryo chimeras

A novel embryo culture media supplement that improves pregnancy rates in mice.

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Highet, A R; Bianco-Miotto, T; Pringle, K G; Peura, A; Bent, S; Zhang, J; Nottle, M B; Thompson, J G; Roberts, C T

2017-03-01

The preimplantation embryo in vivo is exposed to numerous growth factors in the female reproductive tract, which are not recapitulated in embryo culture media in vitro The IGF2 and plasminogen activator systems facilitate blastocyst development. We hypothesized that the addition of IGF2 in combination with urokinase plasminogen activator (uPA) and plasminogen could improve rates of blastocyst hatching and implantation in mice. B6BcF1 and CBAB6F2 mouse embryos were divided into one of four supplemented culture media treatment groups: (1) control (media only); (2) 12.5 nM IGF2; (3) 10 µg/mL uPA and 5 µg/mL plasminogen; or (4) a combination of IGF2, uPA and plasminogen treatments. Embryo development to blastocyst stage and hatching were assessed before transfer to pseudopregnant recipient females and implantation, pregnancy rates and postnatal growth were assessed. After 90.5 h of culture, IGF2 + U + P treatment increased the percentage of B6BcF1 embryos that were hatching/hatched and percentage developing to blastocyst stage compared with controls (P culture, IGF2, uPA and plasminogen supplementation of culture media can improve pregnancy success, but the effect of treatment is dependent on the mouse strain. © 2017 Society for Reproduction and Fertility.

A Simple Method for Transportation of Mouse Embryos Using Microtubes and a Warm Box.

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Mikiko Tokoro

Full Text Available Generally, transportation of preimplantation embryos without freezing requires incubators that can maintain an optimal culture environment with a suitable gas phase, temperature, and humidity. Such incubators are expensive to transport. We reported previously that normal offspring were obtained when the gas phase and temperature could be maintained during transportation. However, that system used plastic dishes for embryo culture and is unsuitable for long-distance transport of live embryos. Here, we developed a simple low-cost embryo transportation system. Instead of plastic dishes, several types of microtubes-usually used for molecular analysis-were tested for embryo culture. When they were washed and attached to a gas-permeable film, the rate of embryo development from the 1-cell to blastocyst stage was more than 90%. The quality of these blastocysts and the rate of full-term development after embryo transfer to recipient female mice were similar to those of a dish-cultured control group. Next, we developed a small warm box powered by a battery instead of mains power, which could maintain an optimal temperature for embryo development during transport. When 1-cell embryos derived from BDF1, C57BL/6, C3H/He and ICR mouse strains were transported by a parcel-delivery service over 3 days using microtubes and the box, they developed to blastocysts with rates similar to controls. After the embryos had been transferred into recipient female mice, healthy offspring were obtained without any losses except for the C3H/He strain. Thus, transport of mouse embryos is possible using this very simple method, which might prove useful in the field of reproductive medicine.

Nucleolus Precursor Bodies and Ribosome Biogenesis in Early Mammalian Embryos: Old Theories and New Discoveries.

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Fulka, Helena; Aoki, Fugaku

2016-06-01

In mammals, mature oocytes and early preimplantation embryos contain transcriptionally inactive structures termed nucleolus precursor bodies instead of the typical fibrillo-granular nucleoli. These nuclear organelles are essential and strictly of maternal origin. If they are removed from oocytes, the resulting embryos are unable to replace them and consequently fail to develop. Historically, nucleolus precursor bodies have been perceived as a passive repository site of nucleolar proteins that are required for embryos to form fully functional nucleoli. Recent results, however, contradict this long-standing dogma and show that these organelles are dispensable for nucleologenesis and ribosome biogenesis. In this article, we discuss the possible roles of nucleolus precursor bodies and propose how they might be involved in embryogenesis. Furthermore, we argue that these organelles are essential only shortly after fertilization and suggest that they might actively participate in centromeric chromatin establishment. © 2016 by the Society for the Study of Reproduction, Inc.

The timing of pronuclear formation, DNA synthesis and cleavage in the human 1-cell embryo.

Science.gov (United States)

Capmany, G; Taylor, A; Braude, P R; Bolton, V N

1996-05-01

The timing of pronuclear formation and breakdown, DNA synthesis and cleavage during the first cell cycle of human embryogenesis are described. Pronuclei formed between 3 and 10 h post-insemination (hpi; median 8 hpi). S-phase commenced between 8 and 14 hpi, and was completed between 10 and 18 hpi. M-phase was observed between 22 and 31 hpi (median duration 3 h), and cleavage to the 2-cell stage took place between 25 and 33 hpi. The timing of the same events was determined in 1-cell embryos derived from re-inseminated human oocytes that had failed to fertilize during therapeutic in-vitro fertilization (IVF). In these embryos, pronuclei formed between 3 and 8 h post-re-insemination (hpr-i), coinciding with the beginning of S-phase. While S-phase was completed as early as 10 hpr-i in some embryos, it extended until at least 16 hpr-i in others. Pronuclear breakdown and cleavage occurred from 23 and 26 hpr-i respectively; however, they did not occur in some embryos until after 46 hpr-i. The results demonstrate a markedly greater degree of variation in the timing of these events in embryos derived from re-inseminated oocytes compared with embryos derived from conventional IVF, and thus throw into question the validity of using the former as models for studies of the first cell cycle of human embryogenesis.

Designer babies on tap? Medical students' attitudes to pre-implantation genetic screening.

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Meisenberg, Gerhard

2009-03-01

This paper describes two studies about the determinants of attitudes to pre-implantation genetic screening in a multicultural sample of medical students from the United States. Sample sizes were 292 in study 1 and 1464 in study 2. Attitudes were of an undifferentiated nature, but respondents did make a major distinction between use for disease prevention and use for enhancement. No strong distinctions were made between embryo selection and germ line gene manipulations, and between somatic gene therapy and germ line gene manipulations. Religiosity was negatively associated with acceptance of "designer baby" technology for Christians and Muslims but not Hindus. However, the strongest and most consistent influence was an apparently moralistic stance against active and aggressive interference with natural processes in general. Trust in individuals and institutions was unrelated to acceptance of the technology, indicating that fear of abuse by irresponsible individuals and corporations is not an important determinant of opposition.

「胚胎植入前基因診斷」之憲法問題Constitutional Issues of “Preimplantation Genetic Diagnosis”

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陳仲妮 Chung-Ni Chen

2009-12-01

Full Text Available 為人父母即使不不奢求「望子成龍，望女成鳳」，至少也希望生下健康的下一代，特別是本身是重大遺傳性疾病的患者。這在過去，僅能藉由懷孕後的絨毛膜或羊膜穿刺等技術進行檢測。上世紀末，本世紀初以來，透過「胚胎植入前基因診斷」，讓「天擇」變成有「人擇」的可能。父母在胚植入子宮前，就可預先篩選「健康」的胚胎。從優生學的角度觀察，這無疑是一大福音；然若全面開放這種「扮演上帝」的技術，懷孕將如同在胚超級市場採購，甚至還有「訂製」的可能，更遑論將碰觸「人性尊嚴」、「生命權」及「生育自決權」等橫跨宗教、倫理、醫學及法律等領域，既嚴肅又難解的課題。對此，世界各國目前的態度不一。本文將從憲法的角度探討此議題，並提出個人淺見。 A healthy baby is not a granted wish for parents especially for those suffering from congenital/inherited disorders themselves. In the past, amniocentesis or chorionic villus sampling has been done at 16 wk- or 10 wk-fetus for prenatal diagnosis. From the end of last century to the beginning of this century, timing of performing this type of early diagnosis was pushed further forward by the development of “preimplantation genetic diagnosis (PGD”. This means that parents can choose “healthy” embryos even before they implanted into a uterus. From the view of eugenics, it is a big progress. However, if people abuse this new technology, it may lead to a horrifying situation: everybody can play God’s role – to choose or even order “desired” embryos which maybe healthier, with the right sex, or even with more pleasant or intelligent characters, instead of letting them go through “natural selection” process. Moreover, this human selection process would create unprecedented and very difficult ethical issues of human dignity, fetal rights to

Preimplantation genetic diagnosis: development and regulation.

Science.gov (United States)

Thomas, C

2006-06-01

Pre-implantation genetic diagnosis (PGD) is used to biopsy and analyse embryos created through in vitro fertilisation (IVF) to avoid implanting an embryo affected by a mutation or chromosomal abnormality associated with serious illness. It reduces the chance that the parents will be faced with a difficult decision of whether to terminate the pregnancy, if the disorder is detected during the course of gestation. PGD is widely accepted for this purpose although there have been suggestions that such procedures have the effect of de-valuing persons in the community with disabilities. PGD potentially has other more controversial purposes, including the selection of the sex of the baby for personal preferences such as balancing the family, rather than to avoid a sex-linked disorder. Recently PGD has become available to create a donor child who is Human Leukocyte Antigen (HLA) matched with a sibling in need of stem cell transplant. In most cases the intention is to utilise the cord blood. However, an HLA-matched child could potentially be required to be a donor of tissues and organs throughout life. This may arise should the initial cord blood donation fail for any one of several reasons, such as inadequate cord blood cell dose, graft failure after cord blood transplant, or the recipient child experiencing a recurrence of the original illness after transplant. However, such on-going demands could also arise if a HLA-matched child was fortuitously conceived by natural means. As such, the issue is not PGD, but rather whether to harvest bone marrow or a solid organ from a child. This raises the question of whether there should be limits and procedures to protect such children from exploitation until they achieve sufficient competence to be able to make mature and autonomous decisions about whether to donate, even if the consequence may in some cases be that it is too late to save the sibling. Additionally, the parents may not be able to make a dispassionate decision, when

In vitro development of donated frozen-thawed human embryos in a prototype static microfluidic device: a randomized controlled trial.

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Kieslinger, Dorit C; Hao, Zhenxia; Vergouw, Carlijn G; Kostelijk, Elisabeth H; Lambalk, Cornelis B; Le Gac, Séverine

2015-03-01

To compare the development of human embryos in microfluidic devices with culture in standard microdrop dishes, both under static conditions. Prospective randomized controlled trial. In vitro fertilization laboratory. One hundred eighteen donated frozen-thawed human day-4 embryos. Random allocation of embryos that fulfilled the inclusion criteria to single-embryo culture in a microfluidics device (n = 58) or standard microdrop dish (n = 60). Blastocyst formation rate and quality after 24, 28, 48, and 72 hours of culture. The percentage of frozen-thawed day-4 embryos that developed to the blastocyst stage did not differ significantly in the standard microdrop dishes and microfluidic devices after 28 hours of culture (53.3% vs. 58.6%) or at any of the other time points. The proportion of embryos that would have been suitable for embryo transfer was comparable after 28 hours of culture in the control dishes and microfluidic devices (90.0% vs. 93.1%). Furthermore, blastocyst quality was similar in the two study groups. This study shows that a microfluidic device can successfully support human blastocyst development in vitro under static culture conditions. Future studies need to clarify whether earlier stage embryos will benefit from the culture in microfluidic devices more than the tested day-4 embryos because many important steps in the development of human embryos already take place before day 4. Further improvements of the microfluidic device will include parallel culture of single embryos, application of medium refreshment, and built-in sensors. NTR3867. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

High Aneuploidy Rates Observed in Embryos Derived from Donated Oocytes are Related to Male Aging and High Percentages of Sperm DNA Fragmentation

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Javier García-Ferreyra

2015-01-01

Full Text Available Capsule Male aging effects on aneuploidy rates in embryos. Objective Paternal age is associated with decreasing sperm quality; however, it is unknown if it influences chromosomal abnormalities in embryos. The objective of this study is to evaluate if the aneuploidy rates in embryos are affected by advanced paternal age. Methods A total of 286 embryos, obtained from 32 in vitro fertilization/intracytoplasmic sperm injection cycles with donated oocytes in conjunction with preimplantation genetic diagnosis, were allocated according to paternal age in three groups: Group A: ≤39 years (n = 44 embryos; Group B: 40-49 years (n = 154 embryos; and Group C: ≥50 years (n = 88 embryos. Fertilization rates, embryo quality at day 3, blastocyst development, and aneuploidy embryo rates were then compared. Results There was no difference in the seminal parameters (volume, concentration, and motility in the studied groups. Fertilization rate, percentages of zygotes underwent cleavage, and good quality embryos on day 3 were similar between the three evaluated groups. The group of men ≥50 years had significantly more sperm with damaged DNA, low blastocyst development rate, and higher aneuploidy rates in embryos compared to the other two evaluated groups ( P 50 years old.

Die Behandlung menschliches Embryos und Menschenwurde

OpenAIRE

Matsui, Fumio

2002-01-01

We are confronted with an old and new problem, which has come up with the progress of modern biotechnologies: what is a life or when does a life begin? The expectation of order-made medicine has build up since the discovery of Embryo Stem cell called "a dream master cell", while there is any condemnation against the destruction of human embryo in order to gain it. It is a question whether a human embryo is a human being in the world. Human dignity(=HD) is a principle that keeps human embryos ...

Preliminary analysis of numerical chromosome abnormalities in reciprocal and Robertsonian translocation preimplantation genetic diagnosis cases with 24-chromosomal analysis with an aCGH/SNP microarray.

Science.gov (United States)

Xie, Yanxin; Xu, Yanwen; Wang, Jing; Miao, Benyu; Zeng, Yanhong; Ding, Chenhui; Gao, Jun; Zhou, Canquan

2018-01-01

The aim of this study was to determine whether an interchromosomal effect (ICE) occurred in embryos obtained from reciprocal translocation (rcp) and Robertsonian translocation (RT) carriers who were following a preimplantation genetic diagnosis (PGD) with whole chromosome screening with an aCGH and SNP microarray. We also analyzed the chromosomal numerical abnormalities in embryos with aneuploidy in parental chromosomes that were not involved with a translocation and balanced in involved parental translocation chromosomes. This retrospective study included 832 embryos obtained from rcp carriers and 382 embryos from RT carriers that were biopsied in 139 PGD cycles. The control group involved embryos obtained from age-matched patient karyotypes who were undergoing preimplantation genetic screening (PGS) with non-translocation, and 579 embryos were analyzed in the control group. A single blastomere at the cleavage stage or trophectoderm from a blastocyst was biopsied, and 24-chromosomal analysis with an aCGH/SNP microarray was conducted using the PGD/PGS protocols. Statistical analyses were implemented on the incidences of cumulative aneuploidy rates between the translocation carriers and the control group. Reliable results were obtained from 138 couples, among whom only one patient was a balanced rcp or RT translocation carrier, undergoing PGD testing in our center from January 2012 to June 2014. For day 3 embryos, the aneuploidy rates were 50.7% for rcp carriers and 49.1% for RT carriers, compared with the control group, with 44.8% at a maternal age < 36 years. When the maternal age was ≥ 36 years, the aneuploidy rates were increased to 61.1% for rcp carriers, 56.7% for RT carriers, and 60.3% for the control group. There were no significant differences. In day 5 embryos, the aneuploidy rates were 24.5% for rcp carriers and 34.9% for RT carriers, compared with the control group with 53.6% at a maternal age < 36 years. When the maternal age was ≥ 36�

Preimplantation Factor (PIF Promotes HLA-G, -E, -F, -C Expression in JEG-3 Choriocarcinoma Cells and Endogenous Progesterone Activity

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Miya Soukaina Hakam

2017-10-01

Full Text Available Background/Aims: Pregnancy success requires mandatory maternal tolerance of the semi/ allogeneic embryo involving embryo-derived signals. Expression levels of PreImplantation Factor (PIF, a novel peptide secreted by viable embryos, correlate with embryo development, and its early detection in circulation correlates with a favourable pregnancy outcome. PIF enhances endometrial receptivity to promote embryo implantation. Via the p53 pathway, it increases trophoblast invasion, improving cell survival / immune privilege. PIF also reduces spontaneous and LPS-induced foetal death in immune naïve murine model. We examined PIF effect on gene expression of human leukocyte antigen (HLA-G, -E -F and –C and the influence of PIF on local progesterone activity in JEG-3 choriocarcinoma cells. Methods: PIF and progesterone (P4 effects on JEG-3 cells surface and intracellular HLA molecules was tested using monoclonal antibodies, flow cytometry, and Western blotting. PIF and IL17 effects on P4 and cytokines secretion was determined by ELISA. PIF and P4 effects on JEG-3 cells proteome was examined using 2D gel staining followed by spot analysis, mass spectrometry and bioinformatic analysis. Results: In cytotrophoblastic JEG-3 cells PIF increased intracellular expression of HLA-G, HLA-F, HLA-E and HLA-C and surface expression of HLA-G, HLA-E and HLA-C in dose and time dependent manner. In case of HLA-E, -F results were confirmed also by Western blot. Proteome analysis confirmed an increase in HLA-G, pro-tolerance FOXP3+ regulatory T cells (Tregs, coagulation factors and complement regulator. In contrast, PIF reduced PRDX2 and HSP70s to negate oxidative stress and protein misfolding. PIF enhanced local progesterone activity, increasing steroid secretion and the receptor protein. It also promoted the secretion of the Th1/Th2 cytokines (IL-10, IL-1β, IL-8, GM-CSF and TGF-β1, resulting in improved maternal signalling. Conclusion: PIF can generate a pro

Preimplantation diagnosis to create 'saviour siblings': a critical discussion of the current and future legal frameworks in South Africa.

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Strode, Ann; Soni, Sheetal

2011-12-14

Pre-implantation genetic diagnosis (PGD) is a technology used in conjunction with in vitro fertilisation to screen embryos for genetic conditions prior to transfer. It was initially developed to screen mutations for severe, irreversible, genetic conditions. Currently, PGD makes it possible to select against more than 100 different genetic conditions. It has been proposed as a method for creating a tissue-matched child who can in turn serve as a compatible stem cell donor to save a sick sibling in need of a stem cell transplant. The advantage of this method is that it provides genetic information before implantation of an embryo into the womb, making it possible to ensure that only tissue-matched embryos are transferred to the uterus. A couple can therefore avoid the difficult choice of either terminating the pregnancy at a later point if the fetus is not a match, or extending their family again in the hope that their next child will be tissue compatible. Many people have expressed disapproval of the use of PGD for this purpose, and it is associated with many conflicting interests including religion, ethics as well as legal regulation. In order to manage these issues some jurisdictions have created legal frameworks to regulate the use of this technology. Many of these are modelled on the UK's Human Fertilisation and Embryology Authority and its guardian legislation. This paper critiques the current and future South African legal framework to establish whether it is able to adequately regulate the use of PGD as well as guard against misuse of the technology. It concludes that changes are required to the future framework in order to ensure that it regulates the circumstances in which PGD may occur and that the Minister of Health should act expediently in finalising draft regulations which will regulate PGD in the future.

The ethics of cloning and human embryo research.

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Saran, Madeleine

2002-01-01

The successful cloning experiments that led to Dolly in 1997 have raised many ethical and policy questions. This paper will focus on cloning research in human embryonic cells. The possible gains of the research will be judged against the moral issues of doing research on a person. This paper concludes that while the embryo has some moral status, its moral status is outweighed by the multitude of benefits that embryonic stem cell research will bring to humanity. Policy suggestions are given for dealing with this new and developing field of stem cell research.

CRISPR/Cas9 as tool for functional study of genes involved in preimplantation embryo development.

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Jeongwoo Kwon

Full Text Available The CRISPR/Cas9 system has proven to be an efficient gene-editing tool for genome modification of cells and organisms. However, the applicability and efficiency of this system in pig embryos have not been studied in depth. Here, we aimed to remove porcine OCT4 function as a model case using the CRISPR/Cas9 system. Injection of Cas9 and single-guide RNA (sgRNA against OCT4 decreased the percentages of OCT4-positive embryos to 37-50% of total embryos, while ~100% of control embryos exhibited clear OCT4 immunostaining. We assessed the mutation status near the guide sequence using polymerase chain reaction (PCR and DNA sequencing, and a portion of blastocysts (20% in exon 2 and 50% in exon 5 had insertions/deletions near protospacer-adjacent motifs (PAMs. Different target sites had frequent deletions, but different concentrations of sgRNA made no impact. OCT4 mRNA levels dramatically decreased at the 8-cell stage, and they were barely detectable in blastocysts, while mRNA levels of other genes, including NANOG, and CDX2 were not affected. In addition, the combination of two sgRNAs led to large-scale deletion (about 1.8 kb in the same chromosome. Next, we injected an enhanced green fluorescent protein (eGFP vector targeting the OCT4 exon with Cas9 and sgRNA to create a knockin. We confirmed eGFP fluorescence in blastocysts in the inner cell mass, and also checked the mutation status using PCR and DNA sequencing. A significant portion of blastocysts had eGFP sequence insertions near PAM sites. The CRISPR/CAS9 system provides a good tool for gene functional studies by deleting target genes in the pig.

Four stages of hepatic hematopoiesis in human embryos and fetuses.

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Fanni, D; Angotzi, F; Lai, F; Gerosa, C; Senes, G; Fanos, V; Faa, G

2018-03-01

The liver is a major hematopoietic organ during embryonic and fetal development in humans. Its hematopoietic activity starts during the first weeks of gestation and continues until birth. During this period the liver is colonized by undifferentiated hematopoietic stem cells (HSCs) that gradually differentiate and once mature, enter the circulatory system through the hepatic sinusoids, this process is called hepatic hematopoiesis. The morphology of hepatic hematopoiesis, has been studied in humans through the years, and led to a characterization of all the cell types that make up these phenomena. Studies on murine models also helped to describe the extent of hepatic hematopoiesis at different gestational ages. Using this knowledge, we attempted to describe how hepatic hematopoiesis morphologically evolves as gestation progresses, in human embryos and fetuses. Thus, we observed a total of 32 tissue specimens obtained from the livers of embryos and fetuses at different gestational ages. Basing our observations on the four stages of liver hematopoiesis identified by Sasaki and Sonoda in mice, we also described four consecutive stages of liver hematopoiesis in humans, which resulted to be highly similar to those described in murine models.

Single-cell duplex RT-LATE-PCR reveals Oct4 and Xist RNA gradients in 8-cell embryos

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Hartung Odelya

2007-12-01

Full Text Available Abstract Background The formation of two distinctive cell lineages in preimplantation mouse embryos is characterized by differential gene expression. The cells of the inner cell mass are pluripotent and express high levels of Oct4 mRNA, which is down-regulated in the surrounding trophectoderm. In contrast, the trophectoderm of female embryos contains Xist mRNA, which is absent from cells of the inner mass. Prior to blastocyst formation, all blastomeres of female embryos still express both of these RNAs. We, thus, postulated that simultaneous quantification of Oct4 and Xist transcripts in individual blastomeres at the 8-cell stage could be informative as to their subsequent fate. Testing this hypothesis, however, presented numerous technical challenges. We overcame these difficulties by combining PurAmp, a single-tube method for RNA preparation and quantification, with LATE-PCR, an advanced form of asymmetric PCR. Results We constructed a duplex RT-LATE-PCR assay for real-time measurement of Oct4 and Xist templates and confirmed its specificity and quantitative accuracy with different methods. We then undertook analysis of sets of blastomeres isolated from embryos at the 8-cell stage. At this stage, all cells in the embryo are still pluripotent and morphologically equivalent. Our results demonstrate, however, that both Oct4 and Xist RNA levels vary in individual blastomeres comprising the same embryo, with some cells having particularly elevated levels of either transcript. Analysis of multiple embryos also shows that Xist and Oct4 expression levels are not correlated at the 8-cell stage, although transcription of both genes is up-regulated at this time in development. In addition, comparison of data from males and females allowed us to determine that the efficiency of the Oct4/Xist assay is unaffected by sex-related differences in gene expression. Conclusion This paper describes the first example of multiplex RT-LATE-PCR and its utility, when

Age of G-1 PLUS v5 embryo culture medium is inversely associated with birthweight of the newborn.

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Kleijkers, Sander H M; van Montfoort, Aafke P A; Smits, Luc J M; Coonen, Edith; Derhaag, Josien G; Evers, Johannes L H; Dumoulin, John C M

2015-06-01

opening of the bottle or batch variations. This indicates a difference of 234 g in birthweight of newborns for media with an age difference of 65 days. The results from this study may be specific for the G-1 PLUS v5 culture medium and extrapolation of the results to other media should be done with caution because of the differences in composition and shelf life. Age of G-1 PLUS v5 medium used to culture human embryos affects birthweight of the respective newborn. This could imply that the preimplantation embryo adapts to its in vitro environment with lasting in vivo consequences. Therefore, it is important that companies are transparent about the exact composition of their embryo culture media, which will allow IVF clinics to further investigate the effects of the media or media components on the health of IVF children. No funding and no competing interests declared. Not applicable. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Conversion and non-conversion approach to preimplantation diagnosis for chromosomal rearrangements in 475 cycles.

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Kuliev, Anver; Janzen, Jeanine Cieslak; Zlatopolsky, Zev; Kirillova, Irina; Ilkevitch, Yury; Verlinsky, Yury

2010-07-01

Due to the limitations of preimplantation genetic diagnosis (PGD) for chromosomal rearrangements by interphase fluorescent in-situ hybridization (FISH) analysis, a method for obtaining chromosomes from single blastomeres was introduced by their fusion with enucleated or intact mouse zygotes, followed by FISH analysis of the resulting heterokaryons. Although this allowed a significant improvement in the accuracy of testing of both maternally and paternally derived translocations, it is still labour intensive and requires the availability of fertilized mouse oocytes, also creating ethical issues related to the formation of interspecies heterokaryons. This method was modified with a chemical conversion procedure that has now been clinically applied for the first time on 877 embryos from PGD cycles for chromosomal rearrangements and has become the method of choice for performing PGD for structural rearrangements. This is presented within the context of overall experience of 475 PGD cycles for translocations with pre-selection and transfer of balanced or normal embryos in 342 (72%) of these cycles, which resulted in 131 clinical pregnancies (38%), with healthy deliveries of 113 unaffected children. The spontaneous abortion rate in these cycles was as low as 17%, which confirms an almost five-fold reduction of spontaneous abortion rate following PGD for chromosomal rearrangements. 2010 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Studies Using an in Vitro Model Show Evidence of Involvement of Epithelial-Mesenchymal Transition of Human Endometrial Epithelial Cells in Human Embryo Implantation*

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Uchida, Hiroshi; Maruyama, Tetsuo; Nishikawa-Uchida, Sayaka; Oda, Hideyuki; Miyazaki, Kaoru; Yamasaki, Akiko; Yoshimura, Yasunori

2012-01-01

Human embryo implantation is a critical multistep process consisting of embryo apposition/adhesion, followed by penetration and invasion. Through embryo penetration, the endometrial epithelial cell barrier is disrupted and remodeled by an unknown mechanism. We have previously developed an in vitro model for human embryo implantation employing the human choriocarcinoma cell line JAR and the human endometrial adenocarcinoma cell line Ishikawa. Using this model we have shown that stimulation with ovarian steroid hormones (17β-estradiol and progesterone, E2P4) and suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor, enhances the attachment and adhesion of JAR spheroids to Ishikawa. In the present study we showed that the attachment and adhesion of JAR spheroids and treatment with E2P4 or SAHA individually induce the epithelial-mesenchymal transition (EMT) in Ishikawa cells. This was evident by up-regulation of N-cadherin and vimentin, a mesenchymal cell marker, and concomitant down-regulation of E-cadherin in Ishikawa cells. Stimulation with E2P4 or SAHA accelerated Ishikawa cell motility, increased JAR spheroid outgrowth, and enhanced the unique redistribution of N-cadherin, which was most prominent in proximity to the adhered spheroids. Moreover, an N-cadherin functional blocking antibody attenuated all events but not JAR spheroid adhesion. These results collectively provide evidence suggesting that E2P4- and implanting embryo-induced EMT of endometrial epithelial cells may play a pivotal role in the subsequent processes of human embryo implantation with functional control of N-cadherin. PMID:22174415

Closure of the vertebral canal in human embryos and fetuses.

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Mekonen, Hayelom K; Hikspoors, Jill P J M; Mommen, Greet; Kruepunga, Nutmethee; Köhler, S Eleonore; Lamers, Wouter H

2017-08-01

The vertebral column is the paradigm of the metameric architecture of the vertebrate body. Because the number of somites is a convenient parameter to stage early human embryos, we explored whether the closure of the vertebral canal could be used similarly for staging embryos between 7 and 10 weeks of development. Human embryos (5-10 weeks of development) were visualized using Amira 3D ® reconstruction and Cinema 4D ® remodelling software. Vertebral bodies were identifiable as loose mesenchymal structures between the dense mesenchymal intervertebral discs up to 6 weeks and then differentiated into cartilaginous structures in the 7th week. In this week, the dense mesenchymal neural processes also differentiated into cartilaginous structures. Transverse processes became identifiable at 6 weeks. The growth rate of all vertebral bodies was exponential and similar between 6 and 10 weeks, whereas the intervertebral discs hardly increased in size between 6 and 8 weeks and then followed vertebral growth between 8 and 10 weeks. The neural processes extended dorsolaterally (6th week), dorsally (7th week) and finally dorsomedially (8th and 9th weeks) to fuse at the midthoracic level at 9 weeks. From there, fusion extended cranially and caudally in the 10th week. Closure of the foramen magnum required the development of the supraoccipital bone as a craniomedial extension of the exoccipitals (neural processes of occipital vertebra 4), whereas a growth burst of sacral vertebra 1 delayed closure until 15 weeks. Both the cranial- and caudal-most vertebral bodies fused to form the basioccipital (occipital vertebrae 1-4) and sacrum (sacral vertebrae 1-5). In the sacrum, fusion of its so-called alar processes preceded that of the bodies by at least 6 weeks. In conclusion, the highly ordered and substantial changes in shape of the vertebral bodies leading to the formation of the vertebral canal make the development of the spine an excellent, continuous staging system for

Live births after polar body biopsy and frozen-thawed cleavage stage embryo transfer: case report.

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Guimarães, Fernando; Roque, Matheus; Valle, Marcello; Kostolias, Alessandra; Azevedo, Rodrigo A de; Martinhago, Ciro D; Sampaio, Marcos; Geber, Selmo

2016-12-01

Pre-implantation genetic diagnosis (PGD) or screening (PGS) technology, has emerged and developed in the past few years, benefiting couples as it allows the selection and transfer of healthy embryos during IVF treatments. These techniques can be performed in oocytes (polar-body biopsy) or embryos (blastomere or trophectoderm biopsy). In this case report, we describe the first two live births to be published in Brazil after a polar-body (PB) biopsy. In case 1, a 42-year-old was submitted to PB biopsy with PGS due to advanced maternal age and poor ovarian reserve. Five MII oocytes underwent first and second polar body biopsy and four cleavage embryos were cryopreserved. The PGS analysis resulted in two euploid embryos (next generation sequence). A frozen-thawed embryo transfer (FET) was performed after endometrial priming and a healthy baby was delivered after a cesarean section (37 weeks, female, 3390g, 47.5 cm). In case 2, a 40-year old patient with balanced translocation and poor ovarian response was submitted to PB biopsy. Two MII oocytes underwent first and second polar body biopsy and two embryos were cryopreserved in cleavage stage. The analysis resulted in one euploid embryo that was transferred after endometrial priming. A preterm healthy baby (34 weeks, female, 2100g, 40 cm) was delivered via cesarean section. In conclusion, although the blastocyst biopsy is the norm when performing PGS/PGD during IVF treatments, other alternatives (as PB biopsy) should be considered in some specific situations.

NGS Analysis of Human Embryo Culture Media Reveals miRNAs of Extra Embryonic Origin.

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Sánchez-Ribas, Immaculada; Diaz-Gimeno, Patricia; Quiñonero, Alicia; Ojeda, María; Larreategui, Zaloa; Ballesteros, Agustín; Domínguez, Francisco

2018-01-01

Our objective in this work was to isolate, identify, and compare micro-RNAs (miRNAs) found in spent culture media of euploid and aneuploid in vitro fertilization (IVF) embryos. Seventy-two embryos from 62 patients were collected, and their spent media were retained. A total of 108 spent conditioned media samples were analyzed (n = 36 day 3 euploid embryos, n = 36 day 3 aneuploid embryos, and n = 36 matched control media). Fifty hed-control media embryos were analyzed using next-generation sequencing (NGS) technology. We detected 53 known human miRNAs present in the spent conditioned media of euploid and aneuploid IVF embryos. miR-181b-5p and miR-191-5p were found the most represented. We validated our results by quantitative polymerase chain reaction (qPCR), but no significant results were obtained between the groups. In conclusion, we obtained the list of miRNAs present in the spent conditioned media from euploid and aneuploid IVF embryos, but our data suggest that these miRNAs could have a nonembryonic origin.

Potent radio-protective effects of vitamins E and C on radiation induced DNA damage in gametes leading to lower frequencies of chromosomal aberrations and micronuclei in subsequent embryos