PDX formation from fresh HCC biopsies were obtained and implanted intrahepatically or in subrenal capsule (SRC). Mouse liver injury was induced in immunodeficient Fah−/− mice through cycling off nitisinone after HCC biopsy implantation, versus continuous nitisinone as non‐liver injury controls. Mice with macroscopically detectable PDX showed rising human alpha1‐antitrypsin (hAAT) serum levels, and conversely, no PDX was observed in mice with undetectable hAAT. The gene discussed is FAH; the disease is hepatocellular carcinoma.