Although Baines KJ et al. reported an elevated level of DEFB1 in COPD and severe asthma, due to the phenotype of asthma being indeterminate, bias may have arisen from asthma phenotypes other than allergic asthma, and the authors did not exclude the allergic condition in healthy controls and COPD populations [17]. The gene discussed is DEFB1; the disease is chronic obstructive pulmonary disease.