Supplementary Material for: Fat Mass- and Obesity-Associated (FTO) Gene and Antipsychotic-Induced Weight Gain: An Association Study

<b><i>Objectives:</i></b> Genetic variation in the fat mass- and obesity-associated gene (FTO) has been associated with obesity in the general population. In this study we have investigated these variants for association with antipsychotic-induced weight gain (AIWG). <b><i>Methods:</i></b> A total of 218 patients with chronic schizophrenia or schizoaffective disorder treated mostly with clozapine or olanzapine for up to 14 weeks were included in the study. We analyzed 4 polymorphisms in intron 1 of the FTO gene (rs1421085, rs8050136, rs9939609, rs9930506) for association with AIWG using ANCOVA. <b><i>Results:</i></b> No statistically significant associations were observed between the single nucleotide polymorphisms and AIWG. However, patients homozygous for the A-allele of rs9939609 gained numerically higher weight than the other genotypic groups (AA: 5.26 ± 6.7%; TA: 4.66 ± 5.6%; TT: 4.21 ± 5.3%). <b><i>Conclusion:</i></b> Our current observations suggest that the FTO gene variants investigated may not play a major role in AIWG.