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Updated: Oct 12, 2025

Using Next Generation Sequencing to Identify Mutations Associated with Repair of a CAS9-induced Double Strand Break Near the CD4 Promoter
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Alternative Lengthening of Telomeres: Lessons to Be Learned from Telomeric DNA Double-Strand Break Repair

Thomas Kent1, David Clynes2

  • 1Molecular Haematology Unit, Radcliffe Department of Medicine, The MRC Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DS, UK.

Genes
|November 27, 2021
PubMed

Insights

The alternative lengthening of telomeres (ALT) pathway in cancer involves deregulated DNA double-strand break (DSB) repair at telomeres, leading to cell immortality. Recent breakthroughs clarify the mechanisms regulating this crucial cancer pathway.

Area of Science:

  • Molecular Biology
  • Cancer Research
  • Genetics

Background:

  • Cancer development is linked to DNA repair pathway dysregulation.
  • Telomere maintenance is crucial for cellular immortality in cancer.
  • The alternative lengthening of telomeres (ALT) pathway is a key mechanism in a subset of cancers.

Purpose of the Study:

  • To provide an in-depth discussion of recent breakthroughs in understanding the ALT pathway.
  • To explore the mechanisms of DNA double-strand break (DSB) repair at telomeres.
  • To highlight the relevance of ALT to cell-cycle regulation and replication fork repair.

Main Methods:

  • Review of recent scientific literature on the ALT pathway.
  • Analysis of molecular mechanisms underlying DSB repair at telomeres.
  • Discussion of cell-cycle-dependent regulation and spatial control of repair processes.

Main Results:

  • Significant progress has been made in elucidating the molecular underpinnings of the ALT pathway.
  • Understanding DSB repair at telomeres provides insights into cancer progression.
  • The regulation of DSB repair is linked to cell-cycle checkpoints and replication fork stability.

Conclusions:

  • The ALT pathway represents a critical target for cancer therapy.
  • Further research into ALT mechanisms can reveal novel therapeutic strategies.
  • Understanding telomere DSB repair is essential for comprehending cancer cell immortality.
Keywords:
ATRXalternative lengthening of telomeresbreak-induced replicationdouble-strand break repairtelomeres

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