Functions as a transcriptional regulator. Functions in cell cycle regulation through CCNA2. Plays an important role in chromosome condensation during the meiotic G2/M transition of spermatocytes. Plays a role in postnatal myogenesis, is involved in satellite cell activation (By similarity). Positively regulates IGF2 expression through PLAG1 and in a PLAG1-independent manner (PubMed:28796236). Interacts with E4F1 (PubMed:14645522). Interacts with NEK2 (By similarity). Additional isoforms seem to exist. Expressed predominantly during embryogenesis. Regulated by cell cycle-dependent phosphorylation which alters its DNA binding affinity. Phosphorylated by NEK2 (By similarity). Genetic variations in HMGA2 define the stature quantitative trait locus 9 (STQTL9) [MIM:611547]. Human height is a classic, highly heritable quantitative trait. The disease is caused by variants affecting the gene represented in this entry. A chromosomal aberration involving HMGA2 is associated with a subclass of benign mesenchymal tumors known as lipomas. Translocation t(3;12)(q27-q28;q13-q15) with LPP is shown in lipomas. HMGA2 is also fused with a number of other genes in lipomas. A chromosomal aberration involving HMGA2 is associated with pulmonary chondroid hamartomas. Translocation t(3;12)(q27-q28;q14-q15) with LPP is detected in pulmonary chondroid hamartomas. A chromosomal aberration involving HMGA2 is associated with parosteal lipomas. Translocation t(3;12)(q28;q14) with LPP is also shown in one parosteal lipoma. A chromosomal aberration involving HMGA2 is found in uterine leiomyoma. Translocation t(12;14)(q15;q23-24) with RAD51B. Chromosomal rearrangements involving HMGA2 do not seem to be the principle pathobiological mechanism in uterine leiomyoma. Belongs to the HMGA family.