Äyräväinen A, Pasanen A, Ahvenainen T, et al. - Researchers investigated the distributions of mediator complex subunit 12 (MED12), high mobility group AT-hook 2 (HMGA2) and fumarate hydratase (FH) aberrations in uterine leiomyomas from fertile-aged myomectomy patients as well as the linked clinical characteristics. They examined a retrospective series of 361 archival uterine leiomyoma samples obtained from 234 women aged ≤ 45 years undergoing myomectomy in 2009–2014. The median age at operation was 34 years. Operation was performed for a single leiomyoma in the majority (58%) of patients. Eighty-three percent of tumors had known driver mutations (71% MED12; 9% HMGA2; 3% FH), indicating that these driver mutations account for the majority of tumors in fertile-aged patients. They observed link of MED12 mutations with multiple tumors, smaller tumor size and subserosal location.