Indeed, 80−90% of leiomyomas harbor one of three genetic changes: a hotspot mutation in mediator complex subunit 12 (MED12), a chromosomal aberration resulting in significant overexpression of high mobility group AT-hook 2 (HMGA2), or biallelic loss of fumarate hydratase (FH). This evidence concerns the gene HMGA2 and leiomyoma.