There was no correlation between γ-H2AX or 53BP1 and age in all samples (Spearman r: .334, p = .345 and Spearman r: .333, p = .318, respectively), indicating that the increased DNA damage in BOEC from healthy smokers and COPD patients is age-independent. The gene discussed is TP53BP1; the disease is chronic obstructive pulmonary disease.