At least 473 Affymetrix HG-U133 +2 Homosapiens probes match one or more species of mycoplasma. Analysis of pub- lished data from thousands of human GeneChips finds correlations in homo sapiens studies between different microbiology laboratories in different countries which suggests contamination with mycoplasma is the common factor. This high lights the problem of experts in evolutionary computation needing to apply due diligence before relying on public medical datasets. Caveat emptor even if the data are free!.