The different liver disease models that have been used are for factor IX deficiency hemophilia B,42 acute intermittent porphyria,43 glycogen storage disease type 1A,44 thrombotic thrombocytopenic purpura,45 alpha-1 antitrypsin deficiency,46 Crigler-Najjar syndrome type 1,47 and urea cycle disorder48 with target genes of FIX, PBGD, glucose-6-phosphatase, ADAMTS13, SERPINA1, bilirubin-UGT, and ornithine transcarbamoylase, respectively. The gene discussed is HMBS; the disease is acute intermittent porphyria.