Sequence comparison of a rat polypeptide GalNAc transferase with an expressed tag sequence database in the GenBank revealed the presence of six discrete C. elegans polypeptide GalNAc transferase homologs.
Preliminary studies indicate that at least one of the isoforms can be functionally expressed.
Our analysis suggests that the polypeptide GalNAc transferase may be an ancestral gene product and the C.elegans genome may encode for a family of at least six distinct isoforms.