Fig. 1

Flowchart of the overall study design. We first used longitudinal follow-up data from the UK Biobank to evaluate the phenotypic association between depression and breast cancer. We then leveraged summary statistics from the hitherto largest genome-wide association study conducted for each trait to characterize the shared genetic architecture through a genome-wide cross-trait analysis. BC: breast cancer; ER: estrogen receptor; GWAS: genome-wide association study; GTEx: Genotype-Tissue Expression project; MR: Mendelian randomization