This is G6PD deficiency.
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.
What is G6PD?
It is glucose phosphate
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.
This particular shunt, HMP shunt,
is responsible for producing your?
So you take the P in the
pentose phosphate pathway
and apply it to what kind
of NAD—not NADH, but NADPH.
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
And what does glutathione do for us?
It then allows for us to then properly
manage and protect ourselves.
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?
Think about a normal mature RBC,
central pallor, it is naked.
It has no nucleus.
It has no mitochondria.
The only method by which it can truly
protect itself is through this HMP shunt.
So it is big deal.
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.
So that’s over two months.
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.
What about a female?
With a female, maybe one X is the mutated
one while the other X is perfectly normal.
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.
The normal 62 drops all
the way down to 13.
That’s not a lot of time for an
enzyme to remain active in one's body.