DNA repair is the process by which cells detect and fix damage in their DNA. It is essential for maintaining genetic stability, which means keeping the genetic information accurate and unchanged through cell divisions.
Here’s how DNA repair helps maintain stability, explained:
1. DNA can get damaged often
DNA is constantly exposed to things that can cause damage — such as sunlight (UV rays), radiation, chemicals, and even normal cell activities.
If this damage is not fixed, it can lead to mutations (changes in DNA), which may cause diseases like cancer or cell death.
2. DNA repair systems fix the damage
Cells have several built-in repair systems that work like a maintenance team to check and correct DNA errors:
- Base excision repair: Fixes small mistakes, like a single damaged base (letter) in DNA.
- Nucleotide excision repair: Removes larger damaged sections, such as those caused by UV light.
- Mismatch repair: Corrects errors made during DNA replication when the wrong base is inserted.
- Double-strand break repair: Repairs breaks in both strands of DNA using methods like homologous recombination or non-homologous end joining.
3. Prevents mutations
By repairing damaged DNA, the cell prevents permanent mutations from being passed on when it divides. This keeps the genetic code accurate and ensures normal cell function.
4. Protects against diseases
Proper DNA repair prevents harmful changes that could lead to cancer, aging-related problems, or genetic disorders.
In short:
DNA repair acts like a proofreading and maintenance system for the genome.
It constantly checks for damage, fixes errors, and keeps the genetic information stable — ensuring that cells function properly and that traits are passed on correctly from one generation to the next.