LIM domain only 2 (rhombotin-like 1), also known as LMO2, RBTNL1, RBTN2, RHOM2, LIM Domain Only Protein 2, TTG2, and T-Cell Translocation Protein 2, is a protein which in humans is encoded by the LMO2 gene. LMO2 encodes a cysteine-rich, two LIM-domain protein that is required for yolk sac erythropoiesis. The LMO2 protein has a central and crucial role in hematopoietic development and is highly conserved. The LMO2 transcription start site is located approximately 25 kb downstream from the 11p13 T-cell translocation cluster (11p13 ttc), where a number T-cell acute lymphoblastic leukemia-specific translocations occur. Alternative splicing results in multiple transcript variants encoding different isoforms.