1-Antitrypsin (A1AT) 2 deficiency is a serious, lifethreatening disorder driven by abnormally low circulating concentrations of A1AT, which lead to protease– antiprotease imbalance. This imbalance accentuates protease activity and can lead to tissue damage, the most important of which leads to impairment of lung function (1 ). The apparent simplicity of diagnosing this disorder by a single meas...