Question

Which of the following can cause mutations that contribute to the development of cancer?

• A. Chemicals in food
• B. UV and ionising radiations
• C. HIV
• D. Reactive oxygen species

Answer 1

Answer: (A), (B), (D)

Reactive oxygen species

Carcinogenic (potentially cancer causing) chemicals can be present in some foods. Ionising and UV radiation can both cause DNA damage. Reactive oxygen species which are generated in cells from molecular oxygen can also modify DNA, causing mutations. Cancers are mainly due to mutations. However, there is no evidence that HIV introduces mutations into cells. Its contribution to the development of cancers is probably that it suppresses the immune response, making immune surveillance less effective.