sj-docx-1-anp-10.1177_00048674221129184 – Supplemental material for The health care cost of comorbidity in individuals with mental disorders: A Danish register-based study

Supplemental material, sj-docx-1-anp-10.1177_00048674221129184 for The health care cost of comorbidity in individuals with mental disorders: A Danish register-based study by Maria K Christensen, John J McGrath, Natalie Momen, Nanna Weye, Esben Agerbo, Carsten Bøcker Pedersen, Oleguer Plana-Ripoll and Kim M Iburg in Australian & New Zealand Journal of Psychiatry</p

Mapping genomic loci implicates genes and synaptic biology in schizophrenia

Schizophrenia has a heritability of 60-80%1, much of which is attributable to common risk alleles. Here, in a two-stage genome-wide association study of up to 76,755 individuals with schizophrenia and 243,649 control individuals, we report common variant associations at 287 distinct genomic loci. Associations were concentrated in genes that are expressed in excitatory and inhibitory neurons of the central nervous system, but not in other tissues or cell types. Using fine-mapping and functional genomic data, we identify 120 genes (106 protein-coding) that are likely to underpin associations at some of these loci, including 16 genes with credible causal non-synonymous or untranslated region variation. We also implicate fundamental processes related to neuronal function, including synaptic organization, differentiation and transmission. Fine-mapped candidates were enriched for genes associated with rare disruptive coding variants in people with schizophrenia, including the glutamate receptor subunit GRIN2A and transcription factor SP4, and were also enriched for genes implicated by such variants in neurodevelopmental disorders. We identify biological processes relevant to schizophrenia pathophysiology; show convergence of common and rare variant associations in schizophrenia and neurodevelopmental disorders; and provide a resource of prioritized genes and variants to advance mechanistic studies