CCR7 and type 1 diabetes mellitus: Together with the observed regulation from a GWAS locus within the CCR region on CCR6+ CCR7− CCR5+ Treg proportion, we tested whether CCR6+ CCR7− CCR5+ Tregs and T1D share the same causal variants/genomic regions by integrating the cell proportion QTL of CCR6+ CCR7− CCR5+ Tregs and the latest T1D GWAS profile via colocalization analysis (Giambartolomei et al., 2014).