n :  a hereditary metabolic disorder affecting red blood cells that is controlled by a variable gene on the X chromosome, that is characterized by a deficiency of glucose-6-phosphate dehydrogenase conferring marked susceptibility to hemolytic anemia which may be chronic, episodic, or induced by certain foods (as broad beans) or drugs (as primaquine), and that occurs esp. in individuals of Mediterranean or African descent .
 
 
 
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