Supplementary Data:

In order to evaluate the efficiency of bisulfite conversion, human genomic DNA with or without

BS-treatment was PCR-amplified with BS primer or non-BS primer (Supplementary Figure 1A)

as the same condition described in materials and methods. The bisulfite-converted genomic DNA

could be PCR-amplified to generate a significant band with BS primer (Lanes 2-3,

Supplementary Figure 2), but not to generate any band with non-BS primer (Lanes 8-16,

Supplementary Figure 2), demonstrating a complete conversion after BS-treatment. In control, a

significant band was generated in non-treated genomic DNA with non-BS primer (Lanes 6-7,

Supplementary Figure 2).

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Supplementary Figure 1 The part sequences of LINE1 element (X8075).(A) Upper lines are shown for original sequences (X8075) and lower for bisulfite-converted

sequences. The positions of primers employed in this study are underlined and grey highlighted.

The primers of BSF and BSR are employed in BS-PCR to generate the template for BS-OLE. The

primers of Non-BSF and Non-BSR are employed in normal PCR to evaluate the BS-conversion

efficiency. (B) The sequences of unmethylated (TG at S1 site, grey-highlight) and methylated (CG

at S1 site) control DNA segments from the cloned plasmid DNAs. Ref. BS-seq. refers to the BS-

PCR product sequences derived from LINE1 original sequences (X8075) as shown in panel A.

The Taq I cleavage site coincided with S1 site is indicated.

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Supplementary Figure 2 Gel-electrophoresis analysis of PCR products amplified from

human genomic DNA with or without BS-treatment.

DNA marker (lane 1); PCR with BS-primer and BS-treated genomic DNA (lane 2 and 3), or no

template control (lane 4); PCR with non BS-primer and no template control (lane 5), non BS-

treated genomic DNA (lanes 6 and 7) or BS-treated DNA (lanes 8-16).

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