NCIt definition : Genes that encode the class of enzymes that catalyze the transfer of glycosyl groups
to an acceptor; often another carbohydrate molecule, a protein, or inorganic phosphate.
Some enzymes in this class catalyze hydrolysis - the transfer of a glycosyl group
to water. Subclasses include Hexosyltransferases, Pentosyltransferases, and Sialyltransferases.
(NCI);