ADAM33 and asthma: Our result found that only the G allele of ADAM33 T1 polymorphism was associated with low-severity (G vs. A: OR = 1.52, 95% CI = 1.02–2.25, P = 0.04) and high-severity asthma (G vs. A: OR = 1.70, 95% CI = 1.05–2.77, P = 0.03) when compared with the controls as shown in Fig. 4.