Fig. 1.

Overview of MethylSaferSeqS. Following ligation of Y-adaptors to each double-stranded DNA molecule during standard library construction, each original strand is copied with a primer that targets the P7 sequence. The primer contains a dual biotin modification and a deoxyuridine (dU) base at the 5′ end. The 5′ biotins allow the copied strand (still hybridized to the original strand) to bind to streptavidin beads. After binding, the original strands are separated from the beads via heat denaturation. The remaining, copied strand is then removed from the beads via cleavage of the deoxyuridine residue at the 5′ end of the primer. This process yields two libraries: one from the copied strands (Left) used for genetic analysis, and the other from original strands (Right) used for epigenetic analysis. UID: Unique identifier. USER: Uracil DNA glycosylase and the DNA glycosylase-lyase Endonuclease VIII.