This study cohort is unique in that it comprises pediatric patients that are drug naive, and therefore an ideal sample in which to test pharmacogenetic predictors of weight gain. In their first 12 weeks on the drugs, one-quarter of the patients gained between 15 to 35 lbs. Patients who were previously treated with antipsychotics may have already gained their initial weight, making it difficult to detect small differences attributable to genetics. This is a beautiful example of how using an intermediate phenotype such as weight gain, which is a continuous variable, compared to the binary case-control GWAS paradigm, yields more powerful associations. I'm looking forward to future studies of MC4R and its potential as a drug target for blocking the metabolic side effects of antipsychotics.

View all comments by Kristin Bigos

As a carer, I know that one of the principal reasons for noncompliance with antipsychotic medications is weight gain. This weight gain also seems to induce diabetes and other physical problems. So it is imperative that this particular aspect is researched more and answers found.

View all comments by Captain Johann Samuhanand