We next applied PEs and BEs to correct a disease-causing mutation in a patient-derived iPSC line carrying a homozygous PiZZ mutation (1024 G > A, E342K) in the serpin family A member 1 (SERPINA1) gene, the most common mutation causing α 1-antitrypsin (A1AT) deficiency (30,31). Here, SERPINA1 is linked to alpha 1-antitrypsin deficiency.