NCIt definition : A ganglioside comprised of a glycosphingolipid (GSL) containing a terminal sialic
acid residue (N-acetylneuraminic acid) that is synthesized by the enzyme ST3 beta-galactoside
alpha-2,3-sialyltransferase 2 (ST3GAL2). This epitope is expressed on the surface
of human embryonic stem cells and human embryonic germ cells. Its expression is turned
off once these cells differentiate during development. Reactivation of expression
is found on the surface of embryonal carcinoma cells.;