HIF1A and hyperinsulinemic hypoglycemia, familial, 4: Yambire and colleagues, [55], showed that insufficient acidification of the endolysosomal system results in a pseudo-hypoxic response (stabilisation of the HIF1-⍺ not due to a low oxygen environment) and the consequent ferrous iron deficiency led to mitochondrial instability and an increase in markers of inflammation.