Of them, 88 (77.2%) patients had the serum AAT levels between 51 mg/dL and 100 mg/dL (might be considered an intermediate AATD), while 26 (22.8%) patients had the serum AAT levels≤ 50mg/dl (a severe AATD). Here, SERPINA1 is linked to alpha 1-antitrypsin deficiency.