REM2 (RAS (RAD and GEM)-like GTP binding 2) is a 340 amino acid cell membrane protein that functions as a GTPase and belongs to the RGK family as well as the small GTPase superfamily. A suppressor of the p53 pathway, REM2 also mediates the fibroblastic growth factor 2 (FGF-2) signaling pathway and is involved in maintaining the proliferation of human embryonic stem cells. Expressed in kidney and brain, REM2 is encoded by a gene that maps to human chromosome 14q11.2. Chromosome 14 encodes the presinilin 1 (PSEN1) gene, which is one of the three key genes associated with the development of Alzheimer's disease (AD). The SERPINA1 gene is also located on chromosome 14 and, when defective, leads to the genetic disorder α1-antitrypsin deficiency, which is characterized by severe lung complications and liver dysfunction.