PTPN2 and type 1 diabetes mellitus: The study by Smyth DJ et al. showed that 21 non-HLA loci were associated with T1DM and 11 non-HLA loci were associated with CD: interestingly, 3 CD loci resulted to have an association with T1DM (RGS1, TAGAP, and IL18RAP) and T1DM loci were also associated with some CD loci (PTPN2 and CCR5) [82].