Research Article A Potential Epigenetic Marker Mediating Serum Folate and Vitamin B12 Levels Contributes to the Risk of Ischemic Stroke

which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Stroke is a multifactorial disease that may be associated with aberrant DNA methylation profiles. We investigated epigenetic dysregulation for themethylenetetrahydrofolate reductase (MTHFR) gene among ischemic stroke patients. Cases and controls were recruited after obtaining signed written informed consents following a screening process against the inclusion/exclusion criteria. Serum vitamin profiles (folate, vitamin B 12, and homocysteine) were determined using immunoassays. Methylation profiles for CpGsA and B in theMTHFR gene were determined using a bisulfite-pyrosequencingmethod.Methylation ofMTHFR significantly increased the susceptibility risk for ischemic stroke. In particular, CpG A outperformed CpG B in mediating serum folate and vitamin B 12 levels to increase ischemic stroke susceptibility risks by 4.73-fold. However, both CpGs A and B were not associated with serum homocysteine levels or ischemic stroke severity. CpG A is a potential epigenetic marker in mediating serum folate and vitamin B 12 to contribute to ischemic stroke. 1