Reaction catalyzed by ganglioside galactosyltransferase (2.4.1.62)

		+			=			+
	UDP-galactose	+		N-acetyl-D-galactosaminyl-(N-acetylneuraminyl)-D-galactosyl-1,4-beta-D-glucosyl-N-acylsphingosine	=		UDP	+		D-galactosyl-1,3-beta-N-acetyl-D-galactosaminyl-(N-acetylneuraminyl)-D-galactosyl-D-glucosyl-N-acylsphingosine