Chromosome breaks and genomic instability

Related Experiment Video

Updated: Oct 9, 2026

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

M Jasin1

  • 1Memorial Sloan-Kettering Cancer Center, Cornell University Graduate School of Medical Sciences, New York, New York, USA. m-jasin@ski.mskcc.org

Cancer Investigation
|March 4, 2000
PubMed

Insights

Disrupting DNA repair pathways, like homologous recombination, can accelerate cancer development by making cells hypermutable. This review explores how impaired DNA repair leads to genetic instability and tumorigenesis.

Area of Science:

  • Genetics
  • Molecular Biology
  • Oncology

Background:

  • Tumorigenesis arises from accumulated genetic alterations.
  • Cells possess DNA repair mechanisms to prevent mutations.
  • Disruption of DNA repair can lead to a hypermutable state, promoting cancer.

Purpose of the Study:

  • To review the role of homologous recombination in DNA repair.
  • To discuss how disruptions in homologous recombination pathways contribute to genetic instability.
  • To explore the link between impaired DNA repair and expedited tumorigenesis.

Main Methods:

  • Literature review of recent studies on homologous recombination.
  • Analysis of the impact of homologous recombination pathway disruption on DNA repair.
  • Synthesis of findings on genetic instability and cancer development.

Main Results:

  • Homologous recombination is crucial for repairing DNA double-strand breaks.
  • Defects in homologous recombination pathways result in a hypermutable cellular phenotype.
  • Genetic instability is a key consequence of disrupted DNA repair mechanisms.

Conclusions:

  • Impaired homologous recombination significantly increases the risk of tumorigenesis.
  • Understanding these pathways is vital for developing cancer therapies.
  • Homologous recombination deficiency is a critical factor in cancer progression.

More Related Videos

Using Next Generation Sequencing to Identify Mutations Associated with Repair of a CAS9-induced Double Strand Break Near the CD4 Promoter06:59

Using Next Generation Sequencing to Identify Mutations Associated with Repair of a CAS9-induced Double Strand Break Near the CD4 Promoter

Published on: March 31, 2022

Capturing Common Fragile Site Breaks by Native γH2A.X ChIP09:46

Capturing Common Fragile Site Breaks by Native γH2A.X ChIP

Published on: January 24, 2025

Related Concept Videos

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...
Homologous Recombination02:31

Homologous Recombination

The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...
Restarting Stalled Replication Forks02:37

Restarting Stalled Replication Forks

DNA replication is initiated at sites containing predefined DNA sequences known as origins of replication. DNA is unwound at these sites by the minichromosome maintenance (MCM) helicase and other factors such as Cdc45 and the associated GINS complex.The unwound single strands are protected by replication protein A (RPA) until DNA polymerase starts synthesizing DNA at the 5’ end of the strand in the same direction as the replication fork. To prevent the replication fork from falling apart, a...
Gene Conversion02:08

Gene Conversion

Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
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...
Homologous Recombination02:31

Homologous Recombination

The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...