The number of CD4+CD25+FOXP3 Tregs in the bronchial biopsies [51] or lungs [52] of patients with stable COPD is not significantly different compared with healthy controls but is decreased in the small airways of COPD patients, and this negatively correlates with the degree of airflow obstruction [47]. The gene discussed is FOXP3; the disease is chronic obstructive pulmonary disease.