The whole-genome oligonucleotide microarray analysis of peripheral blood samples can contribute to the determination of distant blood markers of local pathophysiological alterations in colorectal diseases. These markers can lead to alternative screening procedures. Keywords: whole genomic expression Overall design: Total RNA was extracted from peripheral blood samples of healthy patients and patients with CRC and hybridized on Affymetrix HGU133 Plus 2.0 microarrays