> What about peripheral blood where one may be measuring a signal from a variety of cell types or tissues? This would probably prove useful to you - I've played around with it, and ~450 of their training set probes are on the 450k. You can email the authors for their code. http://www.biomedcentral.com/1471-2105/13/86/abstract >switching from 0.1% methylated to 99.9% methylated is probably a real effect. Switching from 1% to 3% across the board is probably technical artifacts. I think its unclear what these effects do (if anything). Effect sizes less than 1% (which get published) are probably less likely to be real, but these 1-3% effect size hits often replicate in external populations, even if the cpg has no effect on gene expression. -Andrew [[alternative HTML version deleted]]