TY - JOUR
T1 - Concordant fetal hemoglobin response to hydroxyurea in siblings with sickle cell disease
AU - Steinberg, Martin H.
AU - Voskaridou, Ersi
AU - Kutlar, Abdullah
AU - Loukopoulos, Dimitris
AU - Koshy, Mabel
AU - Ballas, Samir K.
AU - Castro, Oswaldo
AU - Barton, Franca
PY - 2003/2/1
Y1 - 2003/2/1
N2 - Fetal hemoglobin (HbF) level and the HbF responses to hydroxyurea (HU) vary among patients with sickle cell disease and are, at least in part, genetically regulated. We hypothesized that siblings with sickle cell disease are likely to share the same parental β-like globin gene clusters with their cis-acting regulatory sequences and therefore, if regulation of this response is linked to the β-globin gene cluster, might have concordant HbF responses to HU. Accordingly, we studied 26 families (30 sib pairings), 20 with sickle cell anemia (three families had three siblings) and 6 families with HbS-β-thalassemia (one family had three siblings, and one family consisted of monozygotic twins), to see if siblings with sickle cell disease had discordant or concordant changes in HbF during HU treatment. Intraclass correlation coefficients (r) showed a high, positive correlation between sibs for HbF levels before and during HU treatment and a concordant change in HbF response from baseline to treatment-associated levels. Changes in mean corpuscular volume (MCV) paralleled HbF levels, while the expected correlations between treatment-associated fall in leukocyte count and increase in MCV were also present. Our results provide additional evidence that some elements that regulate HbF expression are linked to the β-globin gene cluster.
AB - Fetal hemoglobin (HbF) level and the HbF responses to hydroxyurea (HU) vary among patients with sickle cell disease and are, at least in part, genetically regulated. We hypothesized that siblings with sickle cell disease are likely to share the same parental β-like globin gene clusters with their cis-acting regulatory sequences and therefore, if regulation of this response is linked to the β-globin gene cluster, might have concordant HbF responses to HU. Accordingly, we studied 26 families (30 sib pairings), 20 with sickle cell anemia (three families had three siblings) and 6 families with HbS-β-thalassemia (one family had three siblings, and one family consisted of monozygotic twins), to see if siblings with sickle cell disease had discordant or concordant changes in HbF during HU treatment. Intraclass correlation coefficients (r) showed a high, positive correlation between sibs for HbF levels before and during HU treatment and a concordant change in HbF response from baseline to treatment-associated levels. Changes in mean corpuscular volume (MCV) paralleled HbF levels, while the expected correlations between treatment-associated fall in leukocyte count and increase in MCV were also present. Our results provide additional evidence that some elements that regulate HbF expression are linked to the β-globin gene cluster.
KW - Globin gene expression
KW - β-thalassemia
KW - γ-globin gene
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U2 - 10.1002/ajh.10264
DO - 10.1002/ajh.10264
M3 - Article
C2 - 12555216
AN - SCOPUS:0037309546
SN - 0361-8609
VL - 72
SP - 121
EP - 126
JO - American Journal of Hematology
JF - American Journal of Hematology
IS - 2
ER -