RESUMEN
We report two cases of hemoglobin Sendagi in a Romanian family residing in Spain: a four-year-old boy and his mother, who had been previously diagnosed with another type of congenital hemolytic anemia and had undergone splenectomy in her country during childhood. The unstable hemoglobin variant, hemoglobin Sendagi, is characterized by decreased oxygen affinity caused by replacement of one of the critical amino acid residues, phenylalanine beta 42 (CD1) of the beta-chain, with valine in the heme pocket, resulting in methemoglobin formation. As a result of migratory movements in Europe, new disease-causing hemoglobin variants are emerging in our country. Here, capillary electrophoresis enabled the identification of the variant and a molecular study was used to establish an accurate diagnosis.