Chromosomal inversions are a form of genetic mutation in which a segment of DNA reverses orientation along a chromosome. Inversions were first discovered over 100 years ago by Drosophila geneticist Alfred Sturtevant, who when mapping the ordering of genes, noticed chromosomal regions that appeared “flipped” between flies. For many decades, outside of fruit flies, we had little information about the abundance and relevance of inversions. However, recently, advances in DNA sequencing technologies, especially the development of long-read sequencing which allows for thousands of DNA base-pairs to be sequenced in a single read, are allowing researchers to identify and characterize inversions in almost any species – from sunflowers to butterflies. Thus, it is an exciting time to study inversions and to test if and how these mutations may contribute to trait variation in organisms.
