The function of ENSG00000143641 (GALNT2, polypeptide N-acetylgalactosaminyltransferase 2) is as follows. Catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. Has a broad spectrum of substrates for peptides such as EA2, Muc5AC, Muc1a, Muc1b. Probably involved in O-linked glycosylation of the immunoglobulin A1 (IgA1) hinge region. Involved in O-linked glycosylation of APOC-III, ANGPTL3 and PLTP. It participates in the regulation of HDL-C metabolism (PubMed:27508872, PubMed:32293671). {ECO:0000269|PubMed:12438318, ECO:0000269|PubMed:16207894, ECO:0000269|PubMed:16434399, ECO:0000269|PubMed:25939779, ECO:0000269|PubMed:27508872, ECO:0000269|PubMed:32293671, ECO:0000269|PubMed:7592619, ECO:0000269|PubMed:9295285}.