Compared to a set of controls propensity-matched for age and sex, those diagnosed with cancer within 2 but not 3 years showed significantly lower IgM/IgD (2 years: P = 0.006, effect size = 0.14; 3 years: P = 0.08, effect size = 0.07) and higher Ig class-switched B cell fractions (2 years: P = 0.02, effect size = 0.12; 3 years: P = 0.07, effect size = 0.07; Fig. 3b). The gene discussed is CD40LG; the disease is cancer.