The high mobility group protein HMGA2 plays an important role as a chromatin component of stem cells and as a protein causally related to the development of a variety of benign tumors (e.g., uterine leiomyomas, lipomas, and pleomorphic adenomas of the salivary glands). Herein, the existence of a highly conserved region within intron 3 of HMGA2 encoding a microRNA is described. The co-expression with HMGA2 suggests that as an intronic microRNA, this microRNA may cooperate with HMGA2 in its physiological and/or aberrant functions.