CD226 and type 1 diabetes mellitus: Notably, the Idd21.1 risk locus of the non-obese diabetic (NOD) mouse model of type 1 diabetes contains the Cd226 gene and is orthologous to the 18q22.2 region containing the human CD226 gene (19), thereby making the NOD mouse a superb in vivo model of CD226 activity in the context of autoimmunity.