Final answer:
Intercalating agents such as acridine orange and ethidium bromide insert themselves between DNA base pairs, causing mutations by leading to insertions or deletions and potentially resulting in frameshift mutations. These agents affect the DNA during replication and can have significant consequences on gene expression.
Step-by-step explanation:
Intercalating agents, such as acridine orange and ethidium bromide, are indeed known to cause mutations by inserting themselves between DNA base pairs. This can create unusual spacing between the nucleotides, leading to a distortion of the DNA helix. The presence of these agents during DNA replication can make DNA polymerase skip adding several nucleotides, causing a deletion, or add extra nucleotides, leading to an insertion. Such insertions or deletions can result in a frameshift mutation, which alters the reading frame of the genetic code and can have significant consequences on gene expression and function.
Different mutagenic effects are associated with various intercalating agents. For instance, combustion products like polycyclic aromatic hydrocarbons are dangerous intercalating agents that can lead to cancer as a result of their mutagenic effects. To contrast, some chemical mutagens, such as alkylating agents, react directly with DNA base pairs and cause miscoding due to the improper addition of alkyl groups.
Cells have mechanisms such as DNA polymerase proofreading activity, mismatch repair, and nucleotide excision repair to correct mutations, but these are not always foolproof, especially in the presence of potent chemical agents. Therefore, the statement is true: intercalating agents can cause mutations by causing insertions or deletions in DNA.