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Nucleic Acids Res. 1997 November 1; 25(21): 4422–4426.
PMCID: PMC147052

Detection and measurement of PCR bias in quantitative methylation analysis of bisulphite-treated DNA.


Methylation analysis of individual cytosines in genomic DNA can be determined quantitatively by bisulphite treatment and PCR amplification of the target DNA sequence, followed by restriction enzyme digestion or sequencing. Methylated and unmethylated molecules, however, have different sequences after bisulphite conversion. For some sequences this can result in bias during the PCR amplification leading to an inaccurate estimate of methylation. PCR bias is sequence dependent and often strand-specific. This study presents a simple method for detection and measurement of PCR bias for any set of primers, and investigates parameters for overcoming PCR bias.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.
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