To further study the association between obesity and baseline immune history to A/H1N1, we compared the BMI distributions of the low-BIH and high-BIH groups ranked by IgG and IgA responses to viruses, proteins and peptides (Fig. 4A to H; Fig. S6A to H). The gene discussed is CD79A; the disease is obesity due to melanocortin 4 receptor deficiency.