The patient’s oldest brother had died at a young age from an unspecified lung disease, while another brother, a 31-year-old heavy smoker with severe COPD, was found to have no alpha-1 globulin fraction on serum protein electrophoresis, an undetectable serum AAT level, and DNA analysis confirmed a homozygous Q0Ourem genotype. This evidence concerns the gene SERPINA1 and lung disorder.