Table 2. Candidate metabolites over- and under-expressed in probands.

Candidate metabolic compounds with under-expressed peaks	Candidate metabolic compounds with over-expressed peaks	Metabolic function
Serine Glycine	α−aminocyclo-propanecarboxylate	Metabolites involved in the activation of the NMDA receptor
Guanidoacetate Dimethylsulfide Phosphocreatine Betaine Diethanolamine Trimethylamine oxide		Metabolites involved in the anabolism and catabolism of glycine and serine via the methionine to cysteine metabolism
Pyruvate	Lactate Acetate	Metabolites involved in the oxygenation system
1,9 Dimethylurate		Metabolite involved in the urine, purine and caffeine metabolism
	Hydroxyisobutyrate Octane	Compounds related to petrol

Abbreviation: NMDA, N-methyl-D-aspartate.

Metabolic candidate compounds directly involved in the NMDA glycine cotransmitter site are in bold.

Metabolic candidate compounds indirectly involved in the NMDA glycine cotransmitter site are in italics.