Supplementary Material for: Effects of Lithium Monotherapy for Bipolar Disorder on Gene Expression in Peripheral Lymphocytes

Background: This study investigated the effect of lithium monotherapy on peripheral lymphocyte gene expression in bipolar disorder (BD). Method: Twenty-two medication-free bipolar subjects (11 hypomanic, 11 depressed) were started on lithium monotherapy. Closely matched healthy subjects (n = 15) were included as controls but did not receive treatment. Blood RNA samples were collected at baseline and after 2 and 8 weeks of treatment. RNA expression was measured using the Affymetrix GeneChip® Human Gene 1.0 ST Array followed by Ingenuity pathways analysis. The results for the contrast of weeks 2 and 8 were not significantly different and were combined. Results: In BD subjects, 56 genes showed significant (false discovery rate Conclusion: Peripheral gene expression may serve as a biomarker of lithium effect.