Plasma
Homocysteine - 2
Enzymes regulating homocysteine levels: (cont’d)
5,10-MTHFR
50% of North Americans
are heterozygous for mutaion of this gene
Required for the
remethylation of homocysteine to methionine in folic acid cycle
Specimen
requirements:
1.7 fold increase in coronary artery
disease
2.5 fold increase in CVA (stroke)
6.8 fold increase in peripheral
artery disease
Clinical
significance of homocysteine levels:
Plasma/serum separated from RBCs
within minutes
10% increase/hour if not separated and protected from light
Plasma/serum protected from light
