What is a mutation in the context of genetics?

In the context of genetics, a mutation refers to changes in the DNA sequence of a gene, which can lead to variations in the expression of that gene. This alteration can occur in various forms, such as substitutions, deletions, or insertions of nucleotides within the gene's sequence. Such changes can impact the coding or regulatory regions of the gene, potentially resulting in different traits or characteristics in an organism.

The significance of mutations lies in their role in evolution and adaptation. While some mutations can be harmful or neutral, others may confer advantages, thereby influencing an organism's survival. Understanding mutations is fundamental in fields such as genetics, evolutionary biology, and medicine, as they can drive diversity within a species.

The other options do not accurately describe mutations in genetics. While some changes may be beneficial or temporary, mutations are specifically defined by their lasting alterations in the genetic code. Environmental factors relate to genetic expression but do not define a mutation itself.