DNA damage in cetaceans: A mini review.

Area of Science:

• Environmental toxicology
• Marine mammal health
• Cancer research

Background:

• DNA damage is crucial for chemical carcinogen-induced tumorigenesis in many species.
• Cetaceans (whales, dolphins, porpoises) have low cancer rates and are difficult to study.
• Both general and specific DNA damage markers are found in cetaceans.

Purpose of the Study:

• To review the evidence of DNA damage in cetaceans.
• To explore the link between DNA damage and cancer in cetaceans.
• To highlight the potential susceptibility of cetaceans to pollution-induced cancer.

Main Methods:

• Literature review of studies on DNA damage and cancer in cetaceans.
• Analysis of DNA damage markers (e.g., chromosomal aberrations, DNA adducts) in cetacean tissues.
• Correlation analysis between pollutant exposure, DNA adducts, and cancer rates.

Main Results:

• Cetaceans exhibit various types of DNA damage, some comparable to humans.
• A high cancer rate in St. Lawrence Estuary beluga whales correlates with polycyclic aromatic hydrocarbon (PAH) exposure and PAH-DNA adducts.
• Linking general DNA damage to cancer in most cetacean populations remains challenging.

Conclusions:

• Cetaceans may accumulate significant DNA damage from environmental pollutants.
• The St. Lawrence beluga whale population serves as a case study for pollution-induced cancer susceptibility.
• Understanding DNA damage and cancer in whales is vital for marine and human health assessment.