The article by Anton et al1 is less positive than it may appear. They find evidence that patients with the Asp40 allele are more likely to respond to naltrexone hydrochloride treatment for alcoholism, but only if they received medical management (MM) alone, not if they also received combined behavioral intervention (CBI). They explain this by saying that CBI
may have compensated for the placebo effect, thereby suppressing the chances of observing a main effect of naltrexone or a genetic interaction.1(p140)