IL-33	interleukin-33
OR	odds ratio
CI	confidence interval
PCR	polymerase chain reaction
RFLP	restriction fragment length polymorphism
HWE	Hardy–Weinberg equilibrium
FEV1	forced expiratory volume in one second
FVC	forced vital capacity
FEV1%	percent predicted forced expiratory volume in one second
GINA	Global Initiative for Asthma
PM2.5	particulate matter with an aerodynamic diameter ≤ 2.5 μm
IgE	immunoglobulin E
ILC2	group 2 innate lymphoid cell
SOCS3	suppressor of cytokine signaling 3