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Deletion type a-thalassemia among brazilian patients with sickle cell anemia

F.F. Costa; M.H. Tavella; M.A. Zago

Departamento de Clínica Médica, Faculdade de Medicina, USP, 14049 Ribeirão Preto, SP, Brasil

ABSTRACT

The genotype a-/a a (heterozygous a^t thalassemia) was demonstrated throught restriction enzyme DNA analysis for 9/41 (22%) of sickle cell anemia patients which indicates a gene frequency of 0.126. MCV for the group with three a genes was lower than that for patients with four a genes. No difference was observed for HbA₂, HbF and total hemoglobin. The data indicate that the deletion type a-thalassemia has a high prevalence among Brazilian Blacks.

Keywords: Deletion type; a-thalassemia; Brazilian; Sickle cell anemia.

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