To further explore the regulatory nature of the schizophrenia associations, we mapped the credible sets (N=108) of causal variants onto sequences with epigenetic markers characteristic of active enhancers in 56 different tissues and cell lines (Supplementary Text). Schizophrenia associations were significantly enriched at enhancers active in brain (Figure 2) but not in tissues unlikely to be relevant to schizophrenia (e.g., bone, cartilage, kidney, and fibroblasts). Brain tissues used to define enhancers consist of heterogeneous populations of cells. Seeking greater specificity, we contrasted genes enriched for expression in neurons and glia using mouse ribotagged lines41. Genes with strong expression in multiple cortical and striatal neuronal lineages were were enriched for associations, providing support for an important neuronal pathology in schizophrenia (Extended Data Figure 4) but this is not statistically more significant than, or exclusionary of, contributions from other lineages42.
