Porphyrias and hemoglobin

[jakov03]

Hello!
I have heard something about porphyrias and after that I have studied the pathogenesis and biochemistry of this illness. I know that it is a metabolic disorder in heme synthesis. But what I really want to know is how this people have hemoglobins at all, if they can not synthesize the heme?
Feel free you can explain by the bichemical method; on the contrary I am alraedy searching for something such like this.

Btw, I am student and sorry for my bad english.
Thank you!

[Babybel56]

The enzymes are not totally inactivated and cause a drop in haemoglobin production, not a complete cut-off. This isn't the main problem with the disease either: they can still function with this amount. Rather it's the accumulation of the precursors (called porphyrins), which are toxic to the body and cause the symptoms of acute porphyria.