Quantification of methylated DNA occurs by the FRET process, in which energy transfers between the fluorescent molecule and the nearby quantum dot. The amount of fluorescence quenching, measured using confocal microscopy, provides a sensitive and accurate measure of DNA methylation. The technique is sensitive enough to enable the investigators to monitor methylation changes after premalignant cells are treated with drugs known to alter methylation patterns. The researchers also note that this technique is amenable to multiplexing, which affords the opportunity to compare multiple samples from the same patient.

This work, which was supported in part by the National Cancer Institute, is detailed in the paper "MS-qFRET: A quantum dot-based method for analysis of DNA methylation." An investigator from the Lovelace Respiratory Research Institute in Albuquerque also participated in this study. An abstract of the paper is available at the journal's Web site. View abstract

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