Table 1.

Breakdown of lipid identifications in plasma and liver samples by one of 31 classes. “Molecular Level” refers to lipids identified with individual fatty acid rather than as a sum composition.

			Plasma				Liver
Lipid Category	Lipid Class	Abbreviation(s)	Count	% of IDd	Molecular Level	% of Class	Count	% of IDd	Molecular Level	% of Class
Fatty Acyl			29	4.6%	29	100.0%	37	5.9%	37	100.0%
	Acyl Carnitine	AC	2	0.3%	2	100.0%	6	1.0%	6	100.0%
	Fatty Acid*	FA	27	4.3%	27	100.0%	31	5.0%	31	100.0%
Glycerolipid			210	33.1%	165	78.6%	185	29.7%	111	60.0%
	Diglyceride	DG, Alkenyl-DG	2	0.3%	2	100.0%	17	2.7%	15	88.2%
	Triglyceride	TG, Alkanyl-TG, Alkenyl-TG	208	32.8%	163	78.4%	168	27.0%	96	57.1%
Phospholipid			287	45.3%	194	67.6%	303	48.6%	238	78.5%
	Cardiolipin	CL	0	0.0%			9	1.4%	8	88.9%
	Lyso-Phosphocholine	Lyso-PC	27	4.3%	27	100.0%	18	2.9%	18	100.0%
	Lyso-Phosphoethanolamine	Lyso-PE	5	0.8%	5	100.0%	10	1.6%	10	100.0%
	Lyso-Phosphoinositol	Lyso-PI	1	0.2%	1	100.0%	3	0.5%	3	100.0%
	Phosphocholine	PC	129	20.3%	69	53.5%	88	14.1%	62	70.5%
	Phosphoethanolamine	PE, PE-NMe2	24	3.8%	22	91.7%	80	12.8%	57	71.3%
	Phosphoglycerol	PG	2	0.3%	2	100.0%	26	4.2%	26	100.0%
	Phosphoinositol	PI	23	3.6%	19	82.6%	23	3.7%	21	91.3%
	Plasmalogen	Plasmanyl-PC, Plasmenyl-PE, Plasmanyl-PE, Plasmenyl-PC	76	12.0%	49	64.5%	46	7.4%	33	71.7%
Sphingolipid			102	16.1%	41	40.2%	96	15.4%	46	47.9%
	Ceramide	Cer[NS], HexCer[NS], HexCer[AP], Cer[NP], Cer[AS], Cer[AP]	40	6.3%	34	85.0%	58	9.3%	39	67.2%
	Ganglioside*	GM2/GM3	13	2.1%	7	53.8%	8	1.3%	6	75.0%
	Sphingomyelin	SM	49	7.7%	0	0.0%	29	4.7%	0	0.0%
	Sphingosine	SP	0	0.0%			1	0.2%	1	100.0%
Sterol Lipid			6	0.9%	6	100.0%	2	0.3%	2	100.0%
	Cholesteryl Ester	CE	6	0.9%	6	100.0%	2	0.3%	2	100.0%
	* hand-identified		Count	% of Total	Molecular Level	% of IDd	Count	% of Total	Molecular Level	% of IDd
		Identified	634	36.8%	435	68.6%	623	39.9%	434	69.7%
		Unidentified	1087	63.2%			939	60.1%
		Total	1721	100.0%			1562	100.0%