Test Details: Glucose-6-phosphate dehydrogenase deficiency is a genetic disorder that affects red blood cells, which carry oxygen from the lungs to tissues throughout the body. In affected individuals, a defect in an enzyme called glucose-6-phosphate dehydrogenase causes red blood cells to break down prematurely. This destruction of red blood cells is called hemolysis and is the most common medical problem associated with glucose-6-phosphate dehydrogenase deficiency.This type of anemia leads to paleness, yellowing of the skin and whites of the eyes (jaundice), dark urine, fatigue, shortness of breath, and a rapid heart rate.