The function of B4GALNT4 (beta-1,4-N-acetyl-galactosaminyltransferase 4, Ensembl gene identifier ENSG00000182272) is as follows. Transfers N-acetylgalactosamine (GalNAc) from UDP-GalNAc to N-acetylglucosamine-beta-benzyl with a beta-1,4-linkage to form N,N'- diacetyllactosediamine, GalNAc-beta-1,4-GlcNAc structures in N-linked glycans and probably O-linked glycans.