Alpha thalassemia and alpha-MRE haplotypes in Uruguayan patients with microcytosis and hypochromia without anemia

Abstract Alpha thalassemia is the most common genetic disorder across the world, being the α -3.7 deletion the most frequent mutation. In order to analyze the spectrum and origin of alpha thalassemia mutations in Uruguay, we obtained a sample of 168 unrelated outpatients with normal hemoglobin levels with microcytosis and hypochromia from two cities: Montevideo and Salto. The presence of α -thalassemia mutations was investigated by gap-PCR, restriction endonucleases analysis and HBA2 and HBA1 genes sequencing, whereas the alpha-MRE haplotypes were investigated by sequencing. We found 55 individuals (32.7%) with α -thalassemia mutations, 51(30.4%) carrying the - α 3.7 deletion, one with the - α 4.2 deletion and three having the rare punctual mutation HBA2:c.-59C>T. Regarding alpha-MRE analysis, we observed a significant higher frequency of haplotype D, characteristic of African populations, in the sample with the - α 3.7 deletion. These results show that α -thalassemia mutations are an important determinant of microcytosis and hypochromia in Uruguayan patients with microcytosis and hypochromia without anemia, mainly due to the - α 3.7 deletion. The alpha-MRE haplotypes and the α -thalassemia mutations spectrum suggest a predominant, but not exclusive, African origin of these mutations in Uruguay.
Source: Genetics and Molecular Biology - Category: Genetics & Stem Cells Source Type: research