National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Glucose-6-phosphate dehydrogenase deficiency



If glucose 6 phosphate dehydrogenase is needed to metabolize carbohydrates and it's missing, then what happens to the sugar in the blood?  Where does it go?

Blood sugar or "glucose" is made when carbohydrates are broken down. Glucose-6-phosphate dehydrogenase is one enzyme involved in the pentose phosphate pathway, a pathway which processes glucose. The main reasons for this pathway is actually not to metabolize dietary sugars but to make ribose-5-phosphate which is important for making DNA and RNA, and to make NADPH which is important for protecting cells from potentially harmful molecules called reactive oxygen species. There are other enzymatic pathways in the body that exist to metabolize dietary sugars, for example the Krebb cycle, so when there is a deficiency of glucose-6-phosphate dehydrogenase the primary concern is for the impact the defeciency may have on the body as a result of a lack of ribose-5-phosphate and NADPH, and not necessarily its affect on blood sugar.[1]

To learn more about how your body metabolizes food visit the Nemours: Kids Health Web site resource page on this topic at the following link:
http://kidshealth.org/parent/general/body_basics/metabolism.html
Last updated: 5/5/2017

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  1. Luzzatto L, Mehta A, Vulliamy T. Glucose 6-Phosphate Dehydrogenase Deficiency. In: Scriver CR, Beaudet AL, Sly WS, Valle D, Childs B, Kinzler KW, Vogelstein B. The Metabolic & Molecular Bases of Inherited Disease 8th ed. New York, NY: McGraw-Hill; 2001;