In our analysis, though we find 2.61 cases of severe AATD (based on the serum AAT levels ≤50 mg/dL) for every 100 AAT determinations, that can consider higher, but it is necessary to remember that individuals tested for AAT concentrations was not systematic and is affected by the choice of the clinicians. The gene discussed is SERPINA1; the disease is alpha 1-antitrypsin deficiency.