A versatile data repository for GWAS summary statistics-based downstream genomic analysis of human complex traits

Genomic data are increasingly recognized as a critical resource for understanding variation in the human phenome and for improving disease diagnostics, prevention, and intervention. Despite the wealth of genome-wide association study (GWAS) results, linking associated variants to causal genes and biological pathways remains a major challenge, limiting the interpretability of complex trait genetics. We present gact, an R package designed to establish a comprehensive, high-quality database of genomic associations for complex human traits and diseases. The package provides a standardized system to collect GWAS summary statistics, perform rigorous quality control, and integrate genetic associations with genes, biological pathways, GTEx expression data, the GWAS Catalog, and drug–gene interactions. The gact package facilitates downstream analyses such as fine-mapping, polygenic score computation, and gene set enrichment, supporting the biological interpretation of complex genomic associations. The infrastructure and data acquisition functionalities of gact allow researchers to explore environment- and disease-specific genetic signals and their mechanistic context. By streamlining the integration of heterogeneous genomic datasets, gact provides a scalable and accessible tool to advance systems-level understanding of human complex traits and diseases.