Similarly, children with T1D or C showed an increased percentage of CD27−CD19+ (T1D: P = 0.007; C: P = 0.030, Fig. 1A) and CD39+ expressing naive B cells (T1D: P = 0.007, C: P = 0.030, Fig. 1B); but a lower percentage of CD38+ expressing naive B cells (T1D: P = 0.040, C: P = 0.038, Fig. 1C) in comparison with the reference children. The gene discussed is ENTPD1; the disease is type 1 diabetes mellitus.