Abstract
Introduction Fetal hemoglobin (HbF) levels play significant role in lowering down the morbidity
and mortality in sickle cell disease (SCD) patients. Coinheritance of heme oxygenase-1
(HMOX1) rs2071746:A > T polymorphism may contribute to variable HbF levels in Indian
SCD patients.
Objective This study was aimed to evaluate the role of HMOX1 polymorphism and its impact on
HbF level in Indian SCD patients.
Materials and Methods One-hundred twenty confirmed cases of SCD and 50 healthy controls were recruited.
Their mean age was 11.5 ± 8.6 years (range: 3–23 years). Quantification of Hb, HbA2,
HbF, and HbS was done by capillary zone electrophoresis. Allele-specific polymerase
chain reaction was used to genotype HMOX1 (rs2071746:A > T) gene polymorphism.
Results Out of the 120 cases of SCD, 65 were hemoglobin sickle-shaped (HbSS) and 55 were
sickle-beta thalassemia (Sβ). Out of 65 HbSS patients, 29 (44.6%) were heterozygous
(AT), 20 (30.76%) were homozygous (TT), and 16 (24.61%) were found wild-type (AA)
genotype. Out of 55 Sβ, 22 (40%) were heterozygous, 18 (32%) were homozygous and 15
(28%) were wild-type. Patients carrying HMOX1 (rs2071746:A > T), AT, and TT genotypes
had less anemia, painful crisis, splenomegaly, hepatomegaly, jaundice, and blood transfusion.
HbF level was found higher in TT genotype (in HbSS the HbF levels was 25.1 ± 4.4;
in sickle-beta thalassemia the HbF levels was 36.1 ± 4.7) than wild-type(AA) and was
statistically significant (p-value <0.001).
Conclusion The TT genotype of the rs2071746:A > T polymorphism was associated with increased
levels of Hb F (p < 0.001). It can serve as a HbF modifier in Indian sickle cell diseases patients.
Keywords
HMOX1 - HPLC - polymorphism - HbF - SCD
