Hemoglobin H Disease and Beta Thalassemia Major Demonstrated Higher Leucocytic DNA Damage

Hemoglobin H disease and beta thalassemia major are the more severe forms of thalassemia with frequent blood transfusion may be required. Iron chelation therapy is usually needed with blood transfusion to avoid iron overload. Oxidative stress mediated by excess iron via Fenton reaction may contribute to cellular DNA damage. This study was to investigate whether HbH and beta thalassemia major patients were suffered from higher oxidative stress in leucocytes. Comet assay was performed to investigate the DNA damage of 40 normal subjects, 40 hemoglobin H disease patients and beta thalassemia major patients. The UV-induced DNA damages of leucocytes were measured. The comet scores calculated by visual scoring under light microscope represented DNA damage. The mean ± standard deviation comet score for normal subjects; HbH disease and beta thalassemia major were 262.9 ± 8.1, 293.9 ± 15.4 and 293.5 ± 7.2 respectively. Results showed that both HbH disease and beta thalassemia major patients had higher DNA damage in white blood cells.