Correlation of Microarray Probes give Evidence for Mycoplasma Contamination in Human Studies

W. B. Langdon

Web pages for RN/12/11

Notice samples suspected of Mycoplasma Contamination (upper figure, Figure 5) are correlated but the rest of GEO is not (lower figure, Figure 6).

Click on images for details of Figures 5 and 6 in technical report RN/12/11. Once there click above diagonal for individual scatter plots and below diagonal to jump into dynamic RNAnet scatter plot with links to metadata in NCBI gene expression omnibus (GEO) for each data point.
    After loading RNAnet scatter plots remember to press plot. Drag blue cross hair to data points of interest then click hyperlinks to access GEO description of experiment (which may include publication details).

covar_colour.html
Figure 5: Pearson correlation expressed as colours for 61 HG-U133 +2 Affymetrix probes which match mycoplasma exactly on 33 samples suspected of mycoplasma contamination

covar_colour_rev.html
Figure 6. Pearson correlation expressed as colours (cf. Figure 5) for same 61 HG-U133 +2 Affymetrix probes which match mycoplasma exactly across rest of HG-U133 +2 data in NCBI's GEO database. (Notice, as expected [15], probes with a run of 4 Gs are correlated.


W.B.Langdon 31 Oct 2012 (last update 7 November 2012)