Immune dysfunction in psychiatric disorders: emerging genomic insights

Psychiatric disorders are polygenic conditions of the mind and brain, yet immune associations emerge across genetic and molecular studies. Some immune signals may reflect assay bias or illness effects; immunogenetic approaches help disentangle cause and correlation. Genetic associations in the extended major histocompatibility complex (MHC) remain of unclear relevance to immunopathogenesis but warrant finer-resolution analysis. Integrating non-MHC risk variants with immunological data especially implicates adaptive immune cells in psychiatric pathogenesis. Epigenetic studies show that resting immune cells carry a 'poised' landscape encoding past exposures and predicting future responses, illuminating how genetic variability shapes illness risk from environmental insults such as stress and infection. While only some patients may have immune-driven symptoms, the tractability and accessibility of the immune system make it a compelling focus for stratification and therapeutics.