Moreover, we anticipate that hyperoxaluria type 1 (PH1, 259900), caused by mutations in the gene alanine‐glyoxylate aminotransferase (AGXT, 604285), cannot be studied in ICOs, since AGXT is not expressed in healthy ICOs under current culturing conditions (Figure S2D). The gene discussed is AGXT; the disease is primary hyperoxaluria type 1.