I think it is because of the draining of the material entering the colon by the right side, I need rko cell line for my low budget  research, I am sure that molecules of that primary material influence epigenetic machinery

Evripidis, good hypothesis. Go ahead to prove it.

I need rko cell line and am on low budget but open to donations

Apart from considerations of mutational environment and microbiota, the proximal and distal colon are from different embryonic lineages. Colleagues of mine have found the gene expression pattern of non-neoplastic colon is different across the proximal-distal axis. From their paper: "...the proximal large intestine develops from the embryonic midgut and is supplied by the superior mesenteric artery, the distal large intestine forms from the embryonic hindgut and is supplied by the inferior mesenteric artery."

http://physiolgenomics.physiology.org/content/33/1/50.full-text.pdf+html

Dear Jason, thanks for pointing me to the nice article. I'm surprised to find that many genes such as UGT1A3, UGT1A8 are expressed higher in the proximal colon relative to the distal colon. Very interesting. 

Thanks Victor. My colleagues were excited in making this finding. The different embryonic lineage suggests there will be DNA methylation differences in developmental genes as well.

how can one apart epigenetics from the enviroment dear Jason?

Hi Evripidis, the developmental epigenetic signature of a tissue is very strong and particularly involves changes in the methylation of transcription factors and homeobox genes.

Cell. 2014 Dec 4;159(6):1352-64. doi: 10.1016/j.cell.2014.11.005.

Paternal diet defines offspring chromatin state and intergenerational obesity.