Patients with COPD and alpha-1 antitrypsin deficiency (AATD), a disease that causes the development of COPD in young populations due to a deficiency in alpha-1 antitrypsin, had a higher prevalence of periodontitis (COPD 95%, AATD 88%) than the prevalence reported by unselected community residents (data were taken from NHANES and the UK Adult Dental Health Survey in 2009), even after accounting for risk factors. The gene discussed is SERPINA1; the disease is alpha 1-antitrypsin deficiency.