Reaction catalyzed by DELTA14-sterol reductase (1.3.1.70)

		+		NADPH	=			+		NADP+
	4,4-dimethyl-5alpha-cholesta-8,14-dien-3beta-ol	+		NADPH	=		4,4-dimethyl-5alpha-cholesta-8-en-3beta-ol	+		NADP+