- Cloned beta 1,4 N-acetylgalactosaminyltransferase synthesizes GA2 as well as gangliosides GM2 and GD2. GM3 synthesis has priority over GA2 synthesis for utilization of lactosylceramide substrate in vivo. Lutz, M.S., Jaskiewicz, E., Darling, D.S., Furukawa, K., Young, W.W. J. Biol. Chem. (1994)