A study recently published in PLOS one (Catechol-O-Methyltransferase val158met Polymorphism Predicts Placebo Effect in Irritable Bowel Syndrome) purports to have found a gene variant that correlates strongly with a placebo response in irritable bowel syndrome (IBS). The study is small and preliminary, but the results are interesting and do raise important questions about placebo responses.
View the original article here: Are placebo responses genetic?