Library-free methylation sequencing with bisulfite padlock probes

The pairing of bisulfite padlock probes with a probe-design algorithm, library-free sequencing and an analysis pipeline provides a flexible and scalable method for quantifying cytosine methylation. Targeted quantification of DNA methylation allows for interrogation of the most informative loci across many samples quickly and cost-effectively. Here we report improved bisulfite padlock probes (BSPPs) with a design algorithm to generate efficient padlock probes, a library-free protocol that dramatically reduces sample-preparation cost and time and is compatible with automation, and an efficient bioinformatics pipeline to accurately obtain both methylation levels and genotypes from sequencing of bisulfite-converted DNA.