gly-12 encodes an experimentally verified UDP-N-acetylglucosamine alpha-3-D-mannoside beta-1,2-N-acetylglucosaminyltransferase I (GnT I), expressed throughout development in many cell types. gly-12 has no obvious function in vivo, since a deletion allele of gly-12 is phenotypically normal even as a double or triple mutant with gly-13 and gly-14 in Caenorhabditis elegans