A capillary electrophoresis UV detection-based method for global genomic DNA methylation assessment in human whole blood

Quantitative analysis of DNA methylation patterns is of special importance in several developmental and pathological situations. The development of simple and robust methods to assess DNA methylation is required to facilitate its measurement and interpretation in clinical practice. We describe a highly reproducible CE-UV method for the separation and detection of cytosine and methylcytosine, after formic acid hydrolysis of DNA extracted from human whole blood. Hydrolyzed samples were dried and successively dissolved with water and then injected into the capillary without sample derivatization procedures. The use of a run buffer containing 50 mmol/L BIS-TRIS propane (BTP) phosphate buffer at pH 3.25 and 60 mmol/L sodium acetate buffer at pH 3.60 (4:1, v/v) allowed a baseline analytes separation within 12 min. Precision tests indicated an elevated reproducibility with an inter-assay CV of 1.98%.