Sickle Cell Disorder Frequency: Hb S / Thalassemia
|Hb S beta thalassemia|
North Africa, India, and the Mediterranean region, especially Greece and Turkey.
Hb S beta-plus thalassemia, type 1 and Hb S beta-minus thalassemia need supportive therapy and may have severe anemia
Hb S beta-plus thalassemia, type 2 requires very little medical attention
Hb SA alpha-plus thalassemia
Common in persons of African ancestry
|Less hemoglobin S produced than in persons with Hb S trait |
|Hb SS-alpha thalassemia (either plus or zero)||African and Mediterranean ancestry||Mild anemia midway in severity between sickle cell disease and trait|
Produce increased levels of Hb F in proportion to the number of alpha gene deletions present. This acts to retard the sickling process.