ABSTRACT
Genetic and environmental factors are believed to pay a role in the variation in clinical severity of sickle cell disease in different populating group. Among these, fetal Hb expression is one such epistatic factor which may ameliorate severity of the disease as it can reduced the polymerization sickle RBCs. The present work was undertaken to look for correlation between severity of the disease and the expression of HbF. A total of 110 sickle cell disease cases in the age group of 2-49 years were studied. The HbF levels varied from 2-24% with mean of 10.53+ 406%. Our findings did not shown any statistically significant correlation between HbF levels and clinical severity. Nevertheless the mean HbF levels were slightly higher in the group of patients not having any history of painful crisis, infections, need for hospitalisation or blood transfusions. Further the levels of HbS were significantly lower when the HbF levels were high (>10%). This suggests that variation in clinical severity in sickle cell disease may be more due to role of other genetic factors like associated alpha thalassaemia and the higher HbF may only offer an added advantage to these patients.