SERPINA1 and alpha 1-antitrypsin deficiency: Most of the published evidence relating to the management of individuals with alpha-1 antitrypsin deficiency (AATD) is based on patients with the PI*ZZ or PI*Znull genotypes, who have a severe deficiency in alpha-1 antitrypsin (AAT), with plasma levels < 11 μM (< 52 mg/dL) compared with the normal range of 19–47 μM (102–254 mg/dL) [1].