(A) Chromosome 3 congenic mice were developed by mating ALR females to NOD males and the offspring were bred to ALR. The progeny were then genotyped to determine ALR and NOD contributing genome on each chromosome. Mice with NOD contributions on Chr. 3 were chosen to breed with ALR mice. This process continued until NOD genome contributions were present only on Chr. 3, leading to the development of ALR.NODc3 congenic mice that had NOD contributing genome between D3Mit177 and D3Mit189. (B) Respiratory burst was evaluated in neutrophils and macrophages isolated from the bone marrow of the NOD, [NODxALR]F1 hybrids, ALR, and ALR.NODc3 mice. (C) SOD1 activity was measured in homogenized liver tissue from NOD, [NODxALR]F1 hybrids, ALR, and ALR.NODc3 mice using the Cayman Chemical SOD Assay Kit (Ann Arbor, MI, USA) following the manufacturer's directions.