Because the roles of Bach1b, Nrf2a and MafK in heme-mediated regulation of exocrine zymogens appear to be highly conserved between zebrafish and human (Fig. 7A), we believe that the acute episodic abdominal pains in these porphyria individuals are likely to stem from decreased production of pancreatic zymogens. Here, GABPA is linked to porphyria.