Individuals with SLE have higher levels of activated naive B cells(CD11c+IgD+CD27−CD21−MTG+CD23−) and the DN2 subset of IgD−CD27− double-negative B cells (DN2 B cells; IgD−CD27−CD11c+T-Bet+CD69+CD21−CD24−CD38−CXCR5−FCRL4−FCRL5+) (45). The gene discussed is TBX21; the disease is systemic lupus erythematosus.