G6PD Deficiency: Etiology

by Carlo Raj, MD

My Notes
  • Required.
Save Cancel
    Learning Material 2
    • PDF
      Slides G6PP Deficiency.pdf
    • PDF
      Download Lecture Overview
    Report mistake

    00:01 This is G6PD deficiency.

    00:03 This is the first enzyme deficiency that we’re going to take a look at under normocytic anemia and we are dealing with, well, hemolytic where you have increased reticulocytosis.

    00:15 What is G6PD? It is glucose phosphate dehydrogenase.

    00:20 Where do you find this enzyme? Well, you find this, well, think about the glycolytic pathway and I want you to branch off the glycolytic pathway and go into what’s known as a hexose monophosphate shunt or HMP shunt.

    00:34 This particular shunt, HMP shunt, is responsible for producing your? NADPH.

    00:41 So you take the P in the pentose phosphate pathway and apply it to what kind of NAD—not NADH, but NADPH.

    00:52 And why do we in normal physiology require NADPH or biochemistry? It’s the fact that we need NADPH so that we can produce proper amounts of glutathione, right? Glutathione.

    01:04 And what does glutathione do for us? It then allows for us to then properly manage and protect ourselves.

    01:10 Why is this so important for the RBC? Well, the RBCs require proper months of NADPH and glutathione so it can protect itself against antioxidants, right? Antioxidants.

    01:22 Think about a normal mature RBC, central pallor, it is naked.

    01:27 It has no nucleus.

    01:28 It has no mitochondria.

    01:30 The only method by which it can truly protect itself is through this HMP shunt.

    01:34 So it is big deal.

    01:36 Now, something that I wish to bring to your attention about this very important rate-limiting enzyme of your HMP shunt is the fact that the half-life of a normal enzyme here is 62 days.

    01:48 So that’s over two months.

    01:50 So what then happens when you have G6PD deficiency? And we’ll talk about this as being an X-linked recessive disease and so therefore a male, such as myself, well, I have no choice, meaning to say that if I was to then inherit the X chromosome, and that’s where the mutation is, then I obviously will have G6PD deficiency.

    02:13 What about a female? With a female, maybe one X is the mutated one while the other X is perfectly normal.

    02:20 So therefore, she would have a trait, are we clear? Now, if there is such a mutation taking place with X-linked recessive, then what then happens to the enzyme? Take a look at the half-life here.

    02:30 The normal 62 drops all the way down to 13.

    02:34 That’s not a lot of time for an enzyme to remain active in one's body.

    About the Lecture

    The lecture G6PD Deficiency: Etiology by Carlo Raj, MD is from the course Hemolytic Anemia – Red Blood Cell Pathology (RBC).

    Included Quiz Questions

    1. Hexose monophosphate shunt pathway
    2. Glycolytic pathway
    3. Oxidative burst
    4. Lipid synthesis
    5. Krebs cycle
    1. Decreased stability of G6PD
    2. Complete depletion of G6PD
    3. Increased half-life of G6PD
    4. Reversal of G6PD functions
    5. Functional impairment of G6PD

    Author of lecture G6PD Deficiency: Etiology

     Carlo Raj, MD

    Carlo Raj, MD

    Customer reviews

    5,0 of 5 stars
    5 Stars
    4 Stars
    3 Stars
    2 Stars
    1  Star