How do mutagens affect DNA replication and transcription?

Mutagens can cause mutations in DNA, affecting both replication and transcription processes.

Mutagens are agents that can cause changes in DNA sequence, leading to mutations. These mutations can occur during DNA replication, where the DNA molecule is copied, or during transcription, where the DNA sequence is used to make RNA. Mutations can range from small changes in a single nucleotide to large-scale deletions or rearrangements of DNA segments.

During DNA replication, mutagens can cause errors in base pairing, leading to the incorporation of incorrect nucleotides into the new strand. This can result in point mutations, where a single nucleotide is changed, or frameshift mutations, where the reading frame of the DNA sequence is altered. These mutations can affect the function of the protein encoded by the gene, leading to changes in cell behaviour or disease.

Similarly, during transcription, mutagens can cause errors in RNA synthesis, leading to the production of abnormal RNA molecules. This can result in non-functional proteins or proteins with altered activity, affecting cellular processes. Mutagens can also cause premature termination of transcription, leading to truncated proteins or loss of gene expression.

Overall, mutagens can have significant effects on DNA replication and transcription, leading to changes in gene expression and cellular behaviour. Understanding the mechanisms of mutagenesis is important for identifying potential environmental hazards and developing strategies to prevent or mitigate their effects.