Discovering Damage Within Our DNA [Infographic]

A look at the most common forms of damage to our DNA and how that damage can affect our bodies.


Quick Facts about DNA

99.5% of your DNA is shared with every other person on the planet!
The structure of DNA was discovered in 1953 by James Watson and Francis Crick.
DNA’s chemical makeup:
  • Adenine (A)
  • Guanine (G)
  • Cytosine (C) 
  • Thymine (T)

DNA Damage vs. DNA Mutation

DNA Damage

  • Recognized by enzymes > Correctly repaired > Replicates healthy DNA

DNA Mutation

  • Not recognized by enzymes > Cannot be repaired > Replicates mutated DNA

Note: Errors during replication or repair of damaged DNA can turn into mutation.

Exploring 4 Types of DNA Damage

Oxidative Damage

Oxidative stress occurs when the body is exposed to too many electrically charged, aggressive oxygen compounds.
How are we exposed?
  • Breathing
  • Ongoing stress 
  • UV light
  • X-Rays

Why is it bad?

  • High levels of oxidative stress can overwhelm the body’s natural defenses and destroy genetic material, resulting in 8-hydroxydeoxyguanosine (8-OHdG), a common marker for oxidative damage.

Possible effects

  • Decreased DNA repair
  • Increased susceptibility to cancer (colon, breast, prostate)

Hydrolytic & Metabolic Damage

Hydrolytic and metabolic processes can naturally result in DNA damage. These naturally occurring damages take place in our bodies more than 60,000 times per day!
How does it happen?
  • Biochemical reactions of various metabolites
  • Overabundance of reactive oxygen species (ROS)
  • ROS: chemically reactive molecules containing oxygen

Why is it bad?

  • This type of damage contributes to a loss of DNA bases called AP (apurinic/apyrimidinic) sites, which are easily mutated.

Possible effects

  • Inhibited transcription
  • Replication of mutated cells
  • Progression of cancer

DNA Strand Break Damage

Strand breaks can occur in one or both of the DNA strands due to ultraviolet light and other types of radiation.
UV-Induced Damage
  • UV-B light > pyrimidine dimers > direct DNA damage
  • Occurs in areas on the body that are directly exposed to UV-B light
  • UV-A light > free radicals > indirect DNA damage
  • Absorbed into Chromophore and travels though body with potential to affect other areas of body (even inner organs)

Possible Effects

  • Mutations
  • Inhibits expression of multiple genes
  • Progression of skin cancers

Toxic Pollutant Damage

How does it happen?

  • Exposure to polycyclic aromatic hydrocarbons (PAHs) which are potent atmospheric pollutants. The following are examples of damaging pollutants.
  • Oil
  • Coal
  • Cigarette smoke
  • Automobile exhaust fumes

Possible Effects

  • Tumor development
  • Permanent mutations
  • Cell transformation

The Real Issue With DNA Damage

When the rate of DNA damage becomes more than the cell can handle, repair errors take place and overwhelm the cell. This disruption can result in:
  • Early senescence (biological aging)
  • Apoptosis (cell death) which can lead to atrophy
  • Cancer (uncontrolled cell growth of the damaged cell)

Tips for Preventing Damage to Your DNA

  • Healthy diet
  • Regular exercise
  • UV protection

Brought to you by Cell Biolabs |