ABSTRACT
Objective To determine the effect of iron deficiency on hemoglobin A2(HbA2) expression in patients with β-thalassemia.Methods The participants were recruited from the out-patient clinics of the Pediatrics Department and Obstetrics Department of Affiliated Hospital of Guilin Medical College and from some β-thalassemia major families.Blood samples from the participants were used for blood smear tests and hemoglobin electrophoresis and to analyze serum ferritin (SF),3 alpha-globin gene deletions,and 17 beta-globin point mutations.Results Of the 408 individuals,304 were assigned to group A (normal controls),26 to group B (iron deficiency),56 to group C (β-thalassemia),and 22 to group D (β-thalassemia combined with iron deficiency). The results for the comparison of the mean HbA2 values among pairs of groups were as follows: group A vs group B,q=5.074 7,P<0.05; group A vs group C,q=37.650 8,P<0.05; group A vs group D,q=16.043 0,P<0.05;group C vs group D,q=7.682 9,P<0.05; Group B vs group D,q=15.806 6,P<0.05. There were no significant correlation between SF and HbA2 in all 4 groups.Conclusions Iron deficiency decreased the HbA2 level in both controls and individuals with β-thalassemia. HbA2 levels decreased significantly in individuals with both β-thalassemia and iron deficiency as compared with β-thalassemia group alone. However,they remained significantly higher than both the control and iron-deficient groups. Therefore,the elevation of HbA2 could be used to diagnose β-thalassemia reliably even in the presence of iron deficiency.