Fusion of a sequence from HEI10 (14q11) to the HMGIC gene at 12q15 in a uterine leiomyoma

Uterine leiomyoma, a benign smooth-muscle tumor of the myometrium, is the m ost commonly encountered neoplasm in women of reproductive age. Band q15 of chromosome 12 is often rearranged in benign mesenchymal tumors such as ute rine leiomyomas, and the HMGIC gene, encoding a protein of the high-mobilit y-group (HMG), is present in that region. Using 3' rapid amplification of c DNA ends (3'RACE) experiments, we isolated an ectopic sequence that was fus ed to HMGIC in a uterine leiomyoma. Cloning of the fusion cDNA identified a gene termed "homo sapiens enhancer of invasion 10" (HE110) as the fusion p artner. Radiation hybrid mapping revealed that the normal location of HE110 is at 14q11. In the fusion transcript the first two exons of the HMGIC gen e, which encode DNA-binding domains, were fused to the 3' portion of the HE 110 gene. This rearrangement implicates HMGIC in the tumorigenesis of uteri ne leiomyoma, and suggests that its fusion HMGIC product mag play a role in mesenchymal differentiation.