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Analyte: Homocysteine, Total
Specimen Type: For information on this assay, please contact PBI.
Biological or Clinical Significance:
Homocysteine is a sulfur containing amino acid that functions as an intermediate in the pathway of methionine and S-adenosylmethionine synthesis. Although methionine is an amino acid that is found in proteins, homocysteine is not. The conversion of homocysteine to methionine requires vitamin B12 and folic acid, and homocysteine catabolism requires vitamin B6 as a cofactor, so deficiencies in these vitamins cause an increase in plasma homocysteine. A large number, but not all, studies suggest that homocysteine is an independent risk factor for atherosclerotic disease and venous thrombosis.