In severe beta thalassemia, the level of fetal hemoglobin
(Hb F) is markedly increased due to the absence of Hb A, and the amount of Hb [A.
Hydroxyurea is a chemotherapeutic agent that increases the production of fetal hemoglobin
and decreases SCD-related complications.
This fetal hemoglobin
effectively counteracts the effects of the sickle mutation.
The variability in clinical severity of [beta]-thalassemia has been attributed to environmental and genetic factors, including [alpha]-triplication, [alpha]-deletion and Hereditary Persistence of Fetal Hemoglobin
(HPFH), HFE variants and some other unknown mutations (1).
KENSINGTON, New South Wales, July 17, 2017 -- By introducing a beneficial natural mutation into blood cells using the gene-editing technique CRISPR, a University of New South Wales-led team of scientists has been able to switch on production of fetal hemoglobin
Is there a threshold level of fetal hemoglobin
that ameliorates morbidity in sickle cell anemia?
Patients without any of these b-globin gene mutations were transfusion dependent and found to have high fetal hemoglobin
Because of the markedly greater affinity of fetal hemoglobin
shortened erythrocyte survival), increased fetal hemoglobin
, carbamylated hemoglobin, iron replacement therapy, and transfusion requirements may interfere with Hb [A.
It has been known for some time that individuals with genetic mutations that persistently elevate fetal hemoglobin
are resistant to the symptoms of sickle cell disease and beta-thalassemia, genetic forms of severe anemia that are common in many regions of the world.
In HBSS disease fetal hemoglobin
(HbF) is a major modulator of polymerization in that the higher the HbF levels, the more benign the clinical and hematologic features of sickle cell anemia .
Sickle-cell syndromes also include sickle-cell trait (HbAS) and sickle-cell anemia, associated with the hereditary persistence of fetal hemoglobin
(HbS/HPFH) (BRASIL, 2001a).