Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Cleavage and Blastulation

Cleavage and Blastulation

After a large-single-celled zygote is produced via fertilization, the process of cleavage occurs while zygotes travel through the uterine tube. Cleavage is a mitotic cell division that does not result in growth. With each round of successive cell division, daughter cells get increasingly smaller.

Nondisjunction

Nondisjunction

Nondisjunction is the failure of homologous chromosomes or sister chromatids to separate correctly and move to the opposite poles of the cells. This produces daughter cells with abnormal chromosome numbers. Nondisjunction is common during anaphase I or anaphase II of meiosis. Mutations in synaptonemal complex proteins that attach homologous chromosomes increase the chances of nondisjunction in anaphase I of meiosis I. In contrast, mutations in topoisomerases and condensins that hold sister...

Nondisjunction

Nondisjunction

During meiosis, chromosomes occasionally separate improperly. This occurs due to failure of homologous chromosome separation during meiosis I or failed sister chromatid separation during meiosis II. In some species, notably plants, nondisjunction can result in an organism with an entire additional set of chromosomes, which is called polyploidy. In humans, nondisjunction can occur during male or female gametogenesis and the resulting gametes possess one too many or one too few chromosomes.

Gastrulation

Gastrulation

Gastrulation establishes the three primary tissues of an embryo: the ectoderm, mesoderm, and endoderm. This developmental process relies on a series of intricate cellular movements, which in humans transforms a flat, “bilaminar disc” composed of two cell sheets into a three-tiered structure. In the resulting embryo, the endoderm serves as the bottom layer, and stacked directly above it is the intermediate mesoderm, and then the uppermost ectoderm. Respectively, these tissue strata will form...

Fertilization

Fertilization

During fertilization, an egg and sperm cell fuse to create a new diploid structure. In humans, the process occurs once the egg has been released from the ovary, and travels into the fallopian tubes. The process requires several key steps: 1) sperm present in the genital tract must locate the egg; 2) once there, sperm need to release enzymes to help them burrow through the protective zona pellucida of the egg; and 3) the membranes of a single sperm cell and egg must fuse, with the sperm...

Zygotic Development And Stem Cell Formation

Zygotic Development And Stem Cell Formation

The development of all multicellular organisms starts with the fusion of haploid cells called sperm and egg to form a diploid zygote. A zygote is a totipotent cell that can develop into a complete organism. The zygote undergoes cell division or cleavage to form an 8-cell mass. Until this stage, the cells are spherical, loosely attached, and remain totipotent. Totipotent cells are capable of developing both the embryonic and the extraembryonic tissues. However, as they continue to divide, they...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

The social formation of fitness: lifetime consequences of prenatal nutrition and postnatal care in a wild mammal population.

Philosophical transactions of the Royal Society of London. Series B, Biological sciences·2023

Same author

PGDIS position statement on the transfer of mosaic embryos 2021.

Reproductive biomedicine online·2022

Same author

Identifying and optimizing human endometrial gene expression signatures for endometrial dating.

Human reproduction (Oxford, England)·2021

Same author

A veil of ignorance can promote fairness in a mammal society.

Nature communications·2021

Same author

Author Correction: Rice plants overexpressing OsEPF1 show reduced stomatal density and increased root cortical aerenchyma formation.

Scientific reports·2019

Same author

PGDIS Position Statement on the Transfer of Mosaic Embryos 2019.

Reproductive biomedicine online·2019

Search research articles

Related Experiment Video

Updated: Jun 5, 2026

Semiconductor Sequencing for Preimplantation Genetic Testing for Aneuploidy

Semiconductor Sequencing for Preimplantation Genetic Testing for Aneuploidy

Published on: August 25, 2019

Aneuploidy in the human blastocyst.

E Fragouli¹, D Wells

¹University of Oxford, Nuffield Department of Obstetrics and Gynaecology, Institute of Reproductive Sciences, Oxford, UK. elpida.fragouli@obs-gyn.ox.ac.uk

Cytogenetic and Genome Research

|January 22, 2011

Summary

Human embryos show high chromosome abnormality rates, impacting fertility and IVF success. Most chromosome errors are detected late, suggesting blastocyst screening may improve assisted reproductive treatments.

Area of Science:

Reproductive biology
Human embryology
Genetics

Background:

Human cleavage stage embryos exhibit significant chromosome abnormalities.
Errors originate from both gametes and post-fertilization mitotic events, causing mosaicism.
High aneuploidy rates may explain low human fertility and assisted reproductive treatment (ART) success.

Purpose of the Study:

To analyze comprehensive cytogenetic data from human blastocysts (5 days post-fertilization).
To investigate the timing of selection against chromosome abnormalities during preimplantation development.
To evaluate the potential of blastocyst aneuploidy screening to enhance ART outcomes.

Main Methods:

Detailed cytogenetic analysis of a large cohort of human blastocysts.

More Related Videos

Protocol for Human Blastoids Modeling Blastocyst Development and Implantation

Protocol for Human Blastoids Modeling Blastocyst Development and Implantation

Published on: August 10, 2022

Using Mouse Oocytes to Assess Human Gene Function During Meiosis I

Using Mouse Oocytes to Assess Human Gene Function During Meiosis I

Published on: April 10, 2018

Related Experiment Videos

Last Updated: Jun 5, 2026

Semiconductor Sequencing for Preimplantation Genetic Testing for Aneuploidy

Semiconductor Sequencing for Preimplantation Genetic Testing for Aneuploidy

Published on: August 25, 2019

Protocol for Human Blastoids Modeling Blastocyst Development and Implantation

Protocol for Human Blastoids Modeling Blastocyst Development and Implantation

Published on: August 10, 2022

Using Mouse Oocytes to Assess Human Gene Function During Meiosis I

Using Mouse Oocytes to Assess Human Gene Function During Meiosis I

Published on: April 10, 2018

Review of clinical results from ART cycles involving blastocyst transfer.

Main Results:

Aneuploidy affects over 50% of blastocysts, indicating limited selection before implantation.
The majority of selection against chromosome abnormalities occurs around implantation.
Clinical data suggests preferential transfer of euploid blastocysts may improve ART success rates.

Conclusions:

Chromosome abnormalities are prevalent in human blastocysts, with selection occurring late in development.
Blastocyst stage aneuploidy screening offers a promising strategy to improve IVF outcomes.
Further research into the mechanisms of chromosome error and selection is warranted.