The majority of the NK cells had a CD56+ CD16+ phenotype (Fig. 1D) and there was no difference between smokers, subjects with mild COPD, or subjects with severe COPD (p = 0.18 for CD56+ CD16+ NK cells and p = 0.80 for CD56+ CD16− NK cells). The gene discussed is NCAM1; the disease is chronic obstructive pulmonary disease.