Verification of OCT4A with ApaI restriction analysis showed that most of the amplified products (excluding sample 6) were OCT4 pseudogenes and together with semi-quantitative measurements of this band and quantitative RT-PCR with OCT4A specific primers we can suggest the increased expression of OCT4 pseudogenes in colorectal cancer (Figs 3, 4 and S4B). This evidence concerns the gene POU5F1 and colorectal cancer.