The online PICS algorithm calculates the most likely causal SNPs given the observed association signal at a locus. For an associated locus, enter the most highly-associated SNP (referred to as the index SNP) and the strength of association. Using 1000 Genomes Project linkage information (phase 3, GRCh38 positions), the algorithm identifies the SNPs that are most likely to be the causal variants responsible for the association (PICS Probability). Allowed SNP formats are RSID, chr:position, and chr:position:ref:alt (for multi-allelic SNPs, which otherwise map to the most frequent ALT allele).