The Pfizer scientists "have thrown down the gauntlet: They claim that the reported Sirtris compounds do not do what they are claimed to do, " pharmaceutical chemist Derek Lowe, wrote recently on his popular In The Pipeline blog.
Then comes the work of screening scads of receptors against compounds to see which ones bind together--and what pattern of receptors get turned on by gardenias.
The compounds that the added genes produce are generally identical to what the body already produces, and the viruses used to insert the new genes are also widely found in humans.