Hemoglobin is an interesting molecule. There are a lot of variations, and even the 'bad' variations aren't always 'bad' for everyone. I believe there is a signi

Hemoglobin is an interesting molecule. There are a lot of variations, and even the 'bad' variations aren't always 'bad' for everyone. I believe there is a significant portion of those with homozygous sickle cell trait (meaning they ought to have full on sickle cell anemia) who don't show any symptoms. I have thalassemia (a similar hemoglobinopathy), but I also carry the hereditary persistence of fetal hemoglobin (I basically have baby blood), which means -- if i were to have sickle cell anemia -- it wouldn't affect me as much, and my anemia symptoms from the thalassemia are greatly lessened. There's a ton of other variations that can ameliorate all these things too. That's just my knowledge on one. In fact, for those with full-on thalassemia (or sickle cell too), they frequently give hydroxyurea, which causes the bone marrow to produce fetal hemoglobin, to aleve the anemia symptoms. It's all very interesting