What does the term inversion refer to in genetics?

In genetics, the term inversion specifically refers to a rearrangement in the structure of a chromosome in which a segment of the chromosome is flipped and then reintegrated in the opposite orientation. This alteration can occur when a single chromosome breaks in two places, and the middle section is reversed before rejoining with the ends.

This structural change can have significant implications for genes located within the inverted segment by altering their expression or function. Inversions do not involve the addition of genetic material (which would be an insertion), nor do they pertain to the relocation of segments between different chromosomes (translocation) or the duplication of sections of DNA (duplication). Thus, the option representing the flipping and reinsertion of a chromosome segment backwards accurately captures the definition and nature of genetic inversion.