NO

-DNA is chemically unstable.

-Bases can be lost or altered (C ⇾ U)by hydrolysis, resulting in abasic sites or mutations

-Chemicals and free radicals (generated by oxidative metabolism)can change base structure and base pairing.

+Note also cyclophosphamide(DNA alkylating agent) and intercalators such as doxorubicin(inserts between bases) are widely used as anticancer drugs)

-Radiation can damage DNA:-UV light produces thymine dimers and melanoma; ionising radiation(X-rays, gamma rays) can break DNA chromosomes → leukaemia

Learn: DNA Structure and Synthesis (The Living Cell)