Antipsychotic induced weight gain: genetics, epigenetics, and biomarkers reviewed.

Antipsychotic-induced weight gain (AIWG) is a prevalent side effect of antipsychotic treatment, particularly with second generation antipsychotics, such as clozapine and olanzapine. At this point, there is virtually nothing that can be done to predict who will be affected by AIWG. However, hope for the future of prediction lies with genetic risk factors. Many genes have been studied for their association with AIWG with a variety of promising findings. This review will focus on genetic findings in the last year and will discuss the first epigenetic and biomarker findings as well. Although there are significant findings in many other genes, the most consistently replicated findings are in the melanocortin 4 receptor (MC4R), the serotonin 2C receptor (HTR2C), the leptin, the neuropeptide Y (NPY) and the cannabinoid receptor 1 (CNR1) genes. The study of genetic risk variants poses great promise in creating predictive tools for side effects such as AIWG.