A genetic inversion is chromosomal mutation that results in an alteration of that chromosome's gene sequence.

Inversions (inversional mutations) occur when a section of a chromosome is broken away and then re-attached to the chromosome in an orientation opposite the original orientation (a 180 degree rotational shift). There are several types of chromosomal inversion that have differentiating (distinguishing) features. If, for example, the inversional mutation includes the centromere it is considered as pericentric inversion. If the inversional mutation does not include the centromeric region (i.e., the area surrounding the centromere) of the chromosome, then the mutation is referred to as a paracentric inversion.

If one of the chromosomes donated by a parent contains an inversion mutation, the offspring organism is an inversion heterozygote. In such heterozygotes, one of the chromosomes contains a reversal in the linear sequence of genes in the inverted segment of the chromosome. The other...