It is well-characterized that disturbed Th1/Th2 balance contribute to the pathogenesis of asthma 11, and Runx3 participates in the differentiation of Th cells 19, 20, therefore we hypothesize that sex hormones might influence asthmatic airway inflammation via modulating Th1/Th2 balance and Runx3 expression. The gene discussed is RUNX3; the disease is asthma.