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

Karyotyping01:17

Karyotyping

Describing the number and physical features of chromosomes can reveal abnormalities that underlie genetic diseases. This description is facilitated by special staining techniques that produce a particular banding pattern on each chromosome. State-of-the-art techniques make this approach even more powerful, enabling the detection of individual genes that cause disease.A Simple Chromosome Staining Technique Provides Valuable Scientific InsightSome genetic diseases can be detected by looking at...
Chromosome Structure02:40

Chromosome Structure

A functional eukaryotic chromosome must contain three elements: a centromere, telomeres, and numerous origins of replication.
The centromere is a DNA sequence that links sister chromatids. This is also where kinetochores, protein complexes to which spindle microtubules attach, are constructed after the chromosome is replicated. The kinetochores allow the spindle microtubules to move the chromosomes within the cell during cell division.
Telomeres consist of non-coding repetitive nucleotide...
Fixing Double-strand Breaks02:04

Fixing Double-strand Breaks

The double-stranded structure of DNA has two major advantages. First, it serves as a safe repository of genetic information where one strand serves as the back-up in case the other strand is damaged. Second, the double-helical structure can be wrapped around proteins called histones to form nucleosomes, which can then be tightly wound to form chromosomes. This way, DNA chains up to 2 inches long can be contained within microscopic structures in a cell. A double-stranded break not only damages...
Fixing Double-strand Breaks02:04

Fixing Double-strand Breaks

The double-stranded structure of DNA has two major advantages. First, it serves as a safe repository of genetic information where one strand serves as the back-up in case the other strand is damaged. Second, the double-helical structure can be wrapped around proteins called histones to form nucleosomes, which can then be tightly wound to form chromosomes. This way, DNA chains up to 2 inches long can be contained within microscopic structures in a cell. A double-stranded break not only damages...
X and Y Chromosomes02:32

X and Y Chromosomes

Among mammals, the gender of an organism is determined by the sex chromosomes. Humans have two sex chromosomes, X and Y. Every human diploid cell has 22 pairs of autosomes and one pair of sex chromosomes. A human female has two X chromosomes, while a male has one X chromosome and one Y chromosome.
The germline cells such as egg and sperm cells carry only half the number of chromosomes, i.e., 22 autosomes and one sex chromosome. All eggs have an X chromosome, while sperm cells can carry an X or...
Sex-linked Disorders01:43

Sex-linked Disorders

Like autosomes, sex chromosomes contain a variety of genes necessary for normal body function. When a mutation in one of these genes results in biological deficits, the disorder is considered sex-linked.

You might also read

Related Articles

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

Sort by
Same author

Neurofibromatosis type 1 in childhood: correlation of MRI findings with intelligence.

Journal of neurology, neurosurgery, and psychiatry·1995
Same author

Anophthalmia with cleft palate and micrognathia: a new syndrome or an unusual presentation of Rubinstein-Taybi syndrome?

Journal of medical genetics·1995
Same author

The concurrence of the blepharophimosis, ptosis, epicanthus inversus syndrome (BPES) and Langer type of mesomelic dwarfism in the same patient. Evidence of the location of Langer type of mesomelic dwarfism at 3q22.3-q23?

Clinical genetics·1995
Same author

Another look at the causes of the windblown hand.

Journal of hand surgery (Edinburgh, Scotland)·1995
Same author

Microcephaly/lymphedema and terminal deletion of the long arm of chromosome 13.

American journal of medical genetics·1995
Same author

Mutations in L1-CAM in two families with X linked complicated spastic paraplegia, MASA syndrome, and HSAS.

Journal of medical genetics·1995

Related Experiment Video

Updated: Jul 9, 2026

Capturing Common Fragile Site Breaks by Native γH2A.X ChIP
09:46

Capturing Common Fragile Site Breaks by Native γH2A.X ChIP

Published on: January 24, 2025

Human chromosome fragility.

T Lukusa1, J P Fryns

  • 1Center for Human Genetics, University of Leuven, Herestraat 49, B-3000 Leuven, Belgium.

Biochimica Et Biophysica Acta
|December 15, 2007
PubMed
Summary
This summary is machine-generated.

Fragile sites are chromosome regions prone to breakage during DNA replication. Molecular characterization reveals they share a common fragility mechanism involving DNA flexibility and secondary structure formation, impacting chromatin and potentially leading to genetic disorders.

More Related Videos

Rapid Analysis of Chromosome Aberrations in Mouse B Lymphocytes by PNA-FISH
07:54

Rapid Analysis of Chromosome Aberrations in Mouse B Lymphocytes by PNA-FISH

Published on: August 19, 2014

A Robust Polymerase Chain Reaction-based Assay for Quantifying Cytosine-guanine-guanine Trinucleotide Repeats in Fragile X Mental Retardation-1 Gene
08:22

A Robust Polymerase Chain Reaction-based Assay for Quantifying Cytosine-guanine-guanine Trinucleotide Repeats in Fragile X Mental Retardation-1 Gene

Published on: September 16, 2019

Related Experiment Videos

Last Updated: Jul 9, 2026

Capturing Common Fragile Site Breaks by Native γH2A.X ChIP
09:46

Capturing Common Fragile Site Breaks by Native γH2A.X ChIP

Published on: January 24, 2025

Rapid Analysis of Chromosome Aberrations in Mouse B Lymphocytes by PNA-FISH
07:54

Rapid Analysis of Chromosome Aberrations in Mouse B Lymphocytes by PNA-FISH

Published on: August 19, 2014

A Robust Polymerase Chain Reaction-based Assay for Quantifying Cytosine-guanine-guanine Trinucleotide Repeats in Fragile X Mental Retardation-1 Gene
08:22

A Robust Polymerase Chain Reaction-based Assay for Quantifying Cytosine-guanine-guanine Trinucleotide Repeats in Fragile X Mental Retardation-1 Gene

Published on: September 16, 2019

Area of Science:

  • Genetics and Molecular Biology
  • Chromosomal Instability
  • Epigenetics

Background:

  • Fragile sites are heritable chromosome regions susceptible to gaps or breaks under specific conditions, particularly during DNA replication inhibition.
  • They are classified as rare (folate-sensitive or non-folate-sensitive) or common (inducible by agents like aphidicolin, BrdU, or 5-azacytidine).
  • Fragile sites represent areas of chromatin that fail to compact properly during mitosis.

Purpose of the Study:

  • To elucidate the molecular mechanisms underlying fragile site formation.
  • To characterize the structural and functional properties of various fragile sites.
  • To explore the clinical implications of fragile sites, including their association with genetic disorders and cancer.

Main Methods:

  • Molecular characterization of rare and common fragile sites.
  • Analysis of DNA repeat sequences, secondary structure formation potential, and chromatin decondensation.
  • Investigation of DNA torsional flexibility and AT-dinucleotide-rich islands in fragile regions.

Main Results:

  • Rare fragile sites (folate-sensitive and non-folate-sensitive) are characterized by expanded DNA repeat sequences (trinucleotide or minisatellite repeats).
  • These expanded repeats can form stable secondary non-B DNA structures and exhibit high flexibility, affecting replication dynamics and nucleosome assembly.
  • Common fragile sites are AT-rich regions with increased DNA torsional flexibility and AT-dinucleotide-rich islands, also capable of forming secondary structures and interfering with chromatin folding.

Conclusions:

  • All cloned fragile sites share a common fragility mechanism involving DNA flexibility, secondary structure formation, and interference with nucleosome assembly.
  • The folate-sensitive rare fragile site FRAXA is clinically significant, associated with Fragile X syndrome, the most common cause of familial mental retardation.
  • Fragile sites, particularly common fragile sites, are implicated in chromosomal rearrangements in cancer and may play a role in neuropsychiatric and developmental disorders.