GWAS summary statistics

Genome-wide association studies (GWASs) on plasma protein abundance, using protein level for individual proteins and module eigengene for protein networks, were conducted in Caucasian participants with QC-ed genotyping data from the UK Biobank. To avoid bias due to participant overlap, separate GWASs for social isolation (N = 297,396) and loneliness (N = 288,696) were performed using a distinct set of Caucasian participants, excluding those involved in the protein-related GWASs. Age, sex, and the first 20 genetic PCs were adjusted for in all GWASs, while protein technical factors were additionally accounted for in GWASs of proteins and protein modules.