Induced hepatocytes were also established from urine cell-derived iPSCs, taken from patients with Wilson disease and MEDNIK syndrome (mental retardation, enteropathy, deafness, peripheral neuropathy, ichthyosis, keratodermia), which are two inherited copper (Cu) metabolism-related liver disorders caused by mutations in ATP7B and AP1S1 genes, respectively [80]. The gene discussed is AP1S1; the disease is MEDNIK syndrome.