Mutation is best defined as
Mutation is defined as stable, heritable modification of nucleotide sequence that alters genetic information encoded in DNA and persists through replication. Unlike physiological fluctuations in gene expression or transient DNA lesions promptly repaired, mutations involve covalent changes in base sequence that are replicated and transmitted to progeny cells. In multicellular organisms, germline mutations enter gametes and segregate in offspring, while somatic mutations remain confined. This heritability distinguishes true mutations from ephemeral damage, underlying evolution, inherited disorde
Ref: Griffiths et al., Introduction to Genetic Analysis, 12th ed., Chapter 14: Principles of Heritable Mutation Definition
