Raju, > I want to know some free tools available on the > internet to find out the gene expression. Have a look here: http://ihome.cuhk.edu.hk/~b400559/arraysoft.html http://faculty.ucr.edu/~tgirke/Links.htm Gerry Jacobsen http://www.contentsoft.de GeneViz v1.1 - free for non-profit academic use