Retraction to: The Pharmacogenomics Journal (2006) 6, 413–420. doi:10.1038/sj.tpj.6500391; published online 25 April 2006

This article has been retracted by the editor because an investigation by the National Institutes of Health concluded that the data represented by Figures 3a and 4 were falsified. SIR, RPB and RNE agree with this retraction. JSR and H-JL could not be reached for comment.