Method(s): LC-MS/MS (1).
What is dimethylglycine?
Dimethylglycine is formed from betaine during the betaine-homocysteine methyltransferase reaction. It is further degraded to monomethylglycine (sarcosine). Plasma dimethylglycine is associated with risk of acute myocardial infarction in patients with stable angina pectoris (2, 3).
Performance of the assay
Lower limit of detection (LOD): 1.25 µmol/L.
Within-day CV: 2.8-3.4 %; between-day CV: 4.5-5.6 %.
Assessment of choline and one-carbon status. Assessment of cardiovascular risk.
Specimen, collection and processing
Matrix: EDTA plasma is preferred if sarcosine is not measured simultaneously.
Volume: Minimum volume is 50 µL, but 200 µL is optimal and allows reanalysis.
Preparation and stability: The blood sample must be centrifuged and the plasma/serum fraction put on ice, and frozen.
Transportation; for general instruction on transportation, click here.
Frozen, on dry ice.
Reported values, interpretation
Reported values: 1.5-4 µmol/L
Intraclass correlation coefficient (ICC): 0.64.
1. Midttun, O., Kvalheim, G., and Ueland, P.M. (2013). High-throughput, low-volume, multianalyte quantification of plasma metabolites related to one-carbon metabolism using HPLC-MS/MS. Anal Bioanal Chem 405, 2009-017.
2. Svingen, G.F., Ueland, P.M., Pedersen, E.K., Schartum-Hansen, H., Seifert, R., Ebbing, M., Løland, K.H., Tell, G.S., and Nygård, O. (2013). Plasma Dimethylglycine and Risk of Incident Acute Myocardial Infarction in Patients With Stable Angina Pectoris. Arterioscler Thromb Vasc Biol 33, 2041-48.
3. Svingen, G.F., Schartum-Hansen, H., Ueland, P.M., Pedersen, E.R., Seifert, R., Ebbing, M., Bønaa, K.H., Mellgren, G., Nilsen, D.W., et al. (2015). Elevated plasma dimethylglycine is a risk marker of mortality in patients with coronary heart disease. Eur J Prev Cardiol 22, 743-752