RAET1E belongs to the RAET1 family, which consists of major histocompatibility complex (MHC) class I-related genes located in a cluster on chromosome 6q24.2-q25.3. RAET1E and RAET1G protein differ from other RAET1 proteins in that they have type I membrane-spanning sequences at their C termini rather than glycosylphosphatidylinositol anchor sequences. This protein functions as a ligand for NKG2D receptor, which is expressed on the surface of several types of immune cells, and is involved in innate adaptive immune responses. Alternatively spliced transcript variants encoding different isoforms have been found for this gene.