Sabah is also the state with the highest incidence of thalassemia, an inherited blood disorder which results in the excessive destruction of red blood cells and anemia. A person suffers from thalassemia major when he/she inherits the causative defective gene from both parents. The relatively high number of sufferers in Sabah is consistent with the fact that this place historically used to have widespread and endemic malaria. Because thalassemias protected Sabahans from malaria due to the blood cells’ easy degradation, the defective gene survived in the population.
Now, tantalizingly, with an effective malaria vaccine, and a widely-accepted routine of checking would-be parents for the thalassemia gene(s), we could be rid of these two diseases in the long term.
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