Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Meiosis I01:49

Meiosis I

216.8K
Meiosis is a carefully orchestrated set of cell divisions, the goal of which—in humans—is to produce haploid sperm or eggs, each containing half the number of chromosomes present in somatic cells elsewhere in the body. Meiosis I is the first such division, and involves several key steps, among them: condensation of replicated chromosomes in diploid cells; the pairing of homologous chromosomes and their exchange of information; and finally, the separation of homologous chromosomes by...
216.8K
Meiosis I03:09

Meiosis I

43.6K
Meiosis is the division of a diploid cell into haploid cells forming sperm and eggs in animals through differentiation. Meiosis I is the first stage of meiosis, where the genetic recombination of homologous chromosomes and the reduction of the ploidy level by half occurs.
Prophase I is the most extended and complex step of meiosis I characterized by synapsis, chromosome pairing, and recombination of the homologous chromosomes. This process is facilitated by a proteinaceous structure called the...
43.6K
Karyotyping01:17

Karyotyping

67.9K
Overview
67.9K
Meiosis vs. Mitosis02:57

Meiosis vs. Mitosis

69.0K
Cell division is necessary for growth and reproduction in organisms. Mitosis aids cell growth and development by dividing somatic cells. In contrast, meiosis causes the division of germ cells and plays an essential role in sexual reproduction. Due to their unique functional requirements, mitosis and meiosis differ from each other in multiple aspects.
Before the start of mitosis and meiosis I, the cell synthesizes DNA, resulting in two homologous copies of each chromosome. DNA synthesis is...
69.0K
Nondisjunction01:21

Nondisjunction

4.7K
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...
4.7K

You might also read

Related Articles

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

Sort by
Same author

'An adrenaline-fueled emergency': a qualitative thematic analysis of reviews of deaths in England where DNACPR (Do Not Attempt Cardiopulmonary Resuscitation) recommendations are not implemented for people with a learning disability.

BMJ open·2026
Same author

Caregiver-Associated Physical Activity Patterns, Dietary Behaviors and Interventional Beliefs in Individuals with Down Syndrome: Insights from a Large European Survey.

Nutrients·2026
Same author

Understanding Obesity in Individuals with Down Syndrome: Caregiver Perceptions, Awareness, and Motivation.

Nutrients·2026
Same author

Promoting Research Excellence in Down Syndrome: Proceedings of the 5th International Conference of the Trisomy 21 Research Society.

Neuromolecular medicine·2026
Same author

Prevalence of multiple morbidities and cancers in individuals with Down syndrome: A matched descriptive study using linked electronic health record data.

PloS one·2026
Same author

Psychometric properties of the Norwegian CAMDEX-DS-II and CAMCOG-DS-II for dementia assessment in adults with Down syndrome: A national multi-site clinical study.

Research in developmental disabilities·2026

Related Experiment Video

Updated: Dec 29, 2025

In Vitro Modeling of Down Syndrome Neurogenesis Using Human-Induced Pluripotent Stem Cells
06:38

In Vitro Modeling of Down Syndrome Neurogenesis Using Human-Induced Pluripotent Stem Cells

Published on: March 7, 2025

878

Down syndrome.

Stylianos E Antonarakis1, Brian G Skotko2,3, Michael S Rafii4

  • 1Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland. stylianos.antonarakis@unige.ch.

Nature Reviews. Disease Primers
|February 8, 2020
PubMed
Summary
This summary is machine-generated.

Down syndrome (DS), caused by trisomy 21, presents complex genetic challenges. Mouse models help unravel gene contributions to DS features, offering hope for therapeutic interventions.

More Related Videos

Generation of Induced Pluripotent Stem Cells from Turner Syndrome 45XO Fetal Cells for Downstream Modelling of Neurological Deficits Associated with the Syndrome
09:39

Generation of Induced Pluripotent Stem Cells from Turner Syndrome 45XO Fetal Cells for Downstream Modelling of Neurological Deficits Associated with the Syndrome

Published on: December 4, 2021

3.4K
In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila
06:41

In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila

Published on: August 20, 2019

14.1K

Related Experiment Videos

Last Updated: Dec 29, 2025

In Vitro Modeling of Down Syndrome Neurogenesis Using Human-Induced Pluripotent Stem Cells
06:38

In Vitro Modeling of Down Syndrome Neurogenesis Using Human-Induced Pluripotent Stem Cells

Published on: March 7, 2025

878
Generation of Induced Pluripotent Stem Cells from Turner Syndrome 45XO Fetal Cells for Downstream Modelling of Neurological Deficits Associated with the Syndrome
09:39

Generation of Induced Pluripotent Stem Cells from Turner Syndrome 45XO Fetal Cells for Downstream Modelling of Neurological Deficits Associated with the Syndrome

Published on: December 4, 2021

3.4K
In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila
06:41

In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila

Published on: August 20, 2019

14.1K

Area of Science:

  • Genetics
  • Developmental Biology
  • Human Biology

Background:

  • Down syndrome (DS) is a genetic condition caused by trisomy 21, characterized by a complex set of clinical features.
  • It is the most common survivable autosomal aneuploidy, compatible with human survival post-term.
  • Understanding the >200 protein-coding genes on chromosome 21 is crucial for deciphering DS pathophysiology.

Purpose of the Study:

  • To leverage mouse models of DS to investigate the role of triplicated genes on chromosome 21.
  • To gain insights into the molecular basis of diverse clinical manifestations in Down syndrome.
  • To explore opportunities for improving understanding of genetic mechanisms in development and function.

Main Methods:

  • Utilizing mouse models that exhibit trisomy of human chromosome 21 or homologous mouse genomic regions.
  • Analyzing the direct and indirect effects of over 200 protein-coding genes on chromosome 21.
  • Correlating genetic findings with clinical features observed in Down syndrome.

Main Results:

  • Mouse models provide valuable insights into gene contributions to DS clinical features.
  • Significant progress has been made in understanding intellectual disability and congenital heart disease risk factors.
  • Observations in DS individuals suggest chromosome 21 genes conferring cancer protection and offer insights into Alzheimer disease pathology.

Conclusions:

  • The complexity of trisomy 21 offers opportunities to study fundamental genetic mechanisms.
  • Clinical trials targeting intellectual disability in DS represent a new era of therapeutic exploration.
  • Research on Down syndrome pathophysiology holds promise for developing novel interventions and improving patient outcomes.