that category. Cell-type specific annotations were also analysed for variants in four histone marks: H3K4me1, H3K4me3, H3K9ac and H3K27ac and these were grouped into 9 cell type groups: central nervous system (CNS), cardiovascular, connective tissue or bone, gastrointestinal, immune or hematopoietic, kidney, liver, skeletal muscle, or other. Given the strong contribution to depression heritability from the CNS we used LDSC applied to specifically expressed genes (LDSC-SEG) 78 across 13 brain regions from the GTEx gene-expression database and brain cell-types (neuronal, astrocyte, oligodendrocyte) using specifically expressed genes derived from mouse-forebrain 79.
