TMIGD1 (transmembrane and immunoglobulin domain containing 1) is a 262 amino acid single-pass membrane protein that contains two Ig-like C2-type (immunoglobulin-like) domains (1,2). It is a nonsecreted, glycosylated protein located in the cytoplasm and cell membrane (1). TMIGD1 might be a possible cell-differentiation marker in the intestine, whose expression is lost during cellular transformation and promote progression of tumorigenesis in the intestinal epithelium (2-4). TMIGD1 has also been postulated to play a role in cell adhesion (2).