DNA methylation profiling in nanochannels

Biomicrofluidics. 2011 Sep;5(3):34106-341068. doi: 10.1063/1.3613671. Epub 2011 Jul 25.

Abstract

We report the profiling of the 5-methyl cytosine distribution within single genomic-sized DNA molecules at a gene-relevant resolution. This method linearizes and stretches DNA molecules by confinement to channels with a dimension of about 250×200 nm(2). The methylation state is detected using fluorescently labeled methyl-CpG binding domain proteins (MBD), with high signal contrast and low background. DNA barcodes consisting of methylated and non-methylated segments are generated, with both short and long concatemers demonstrating spatially resolved MBD binding. The resolution of the technique is better than 10 kbp, and single-molecule read-lengths exceeding 140 kbp have been achieved.