Screening of new genes related to the colorectal carcinoma with suppression subtractive hybridization

Aims To construct cDNA libraries of colorectal carcinoma, and screen and clone the new genes related to the colorectal carcinoma. Methods cDNA fragments of differently expressed genes in colorectal carcinoma and normal intestinal tissues were isolated with suppression subtractive hybridization (SSH). Then these cDNA fragments were directly inserted into T vector to set up the subtractive library. Two hundreds of positive bacteria clones were randomly picked and identified by colony PCR method. Then 50 differently expressed genes were sequenced and analyzed with BLAST program in GenBank wired NCBI website. Some genes were identified by Virtual Northern Blot. Results cDNA library of colorectal carcinoma and normal intestine tissue was successfully constructed, and 20 differently expressed genes were obtained after filtration. Two new genes did not match the identical sequence, and they should be new genes related to the colorectal cancer. Conclusions cDNA library of colorectal carcinoma and normal intestine tissue was constructed by SSH, and 2 new genes related to the colorectal cancer were found.