US6995004B2 - UDP-N-ACETYLGLUCOSAMINE: GALACTOSE-Β 1,3-N-ACETYLGALACTOSAMINE-Α-R / N-ACETYLGLUCOSAMINE-Β 1,3,-N-ACETYLGALACTOSAMINE-Α-R (GLCNAC to GALNAC) Β1,6-N-ACETYLGLUCOSAMINYLTRANSFERASE, C2/4GNT