GSTT1 null genotype in sickle cell anemia and blood transfusion recurrence – a case report
Sickle cell anemia is one of the most common genetic diseases in Brazil. This disease has an autosomal recessive inheritance pattern with a point mutation on chromosome 11, which is the substitution of an adenine by thymine. This mutation leads to the exchange of a glutamic acid for a valine at residue 6 of the beta globin chain, resulting in an abnormal form of hemoglobin, the so-called hemoglobin S (Hb S). The polymerization of Hb S produces reactive oxygen species, oxidizing agents that promote the oxidation of macromolecules, such as lipids, proteins and DNA. GSTs are enzymes that participate in the conjugation reactions of glutathione to a variety of electrolytic compounds that are potentially toxic and carcinogenic. The We analyzed the GSTT1 and GSTM1 gene polymorphisms in a patient with sickle cell anemia in order establish a more efficient clinical approach to treat the patient. The patient under study was 11 years old and sickle cell anemia was confirmed by the Guthrie test. Polymorphism identification was performed by PCR. The genotype identified in the patient was null for GSTT1 and present for GSTM1. In addition, the patient has a recurrent need for blood transfusion.