Whilst naive Ethe1−/− mice displayed marked COX deficiency due to H2S poisoning (Di Meo et al, 2011) in the luminal surface of the colonic mucosa, muscle fibres and brain cells, the AAV treatment was associated with clearly visible, albeit partial, correction to nearly normal levels (Fig 3). This evidence concerns the gene ETHE1 and hyperinsulinemic hypoglycemia, familial, 4.