<prompt> In which condition hemolysis occurs on oxidation?G6PD deficiencyHereditary spherocytosisSickle cell anemiaHemophilia  <response>: ANSWER: A G6PD deficiencyREF: Harrisons 17 editions, chapter 101G6PD DeficiencyGlucose 6-phosphate dehydrogenase G6PD is a housekeeping enzyme critical in the redox metabolism of all aerobic cells. In red cells, its role is even more critical because it is the only source of reduced nicotinamide adenine dinucleotide phosphate NADPH, which, directly and via reduced glutathione GSH, defends these cells against oxidative stress. G6PD deficiency is a prime example of a hemolytic anemia due to interaction between an intra-corpuscular and an extra-corpuscular cause, because in the majority of cases hemolysis is triggered by an exogenous agent. Although in G6PD-deficient subjects there is a decrease in G6PD activity in most tissues, this is less marked than in red cells, and it does not seem to produce symptoms. 