Molecular and hematological spectrum of α-thalassemia in Saudi patients

Abstract

α-thalassemia (α-thal) is a genetic disorder characterized by a decreased synthesis of α-globin chains. A deletion mutation most often causes it in one or more α-globin chains. No comprehensive characterization studies have been conducted on α-thal patients in the Saudi population. Therefore, this research aims to identify the spectrum of genetic mutations responsible for α-thal in our region. Individuals with microcytic, hypochromic red blood cells and normal hemoglobin (Hb) A2 were enrolled. Sixty samples of individuals suspected of α-thal were selected for further genetic analysis. Multiplex ligation-dependent probe amplification assay was used to detect deletion mutations in α-globin genes. Among all samples tested, the -α3.7 deletion mutation was detected in 57 (95%) cases, whereas no mutation was detected in the remaining 3 (5%). In addition, 9 (15%) individuals were heterozygous for -α3.7, while -α3.7 homozygosity was found in 85% of the analyzed cases. The hematological characteristics of α3.7 subjects were significantly lower than the control group in the mean of Hb, hematocrit, mean corpuscular volume, mean corpuscular Hb, and mean corpuscular Hb concentration (p<0.001). These results highlight the importance of α-thal diagnosis and investigation in Saudi Arabia’s pre-marital screening program for microcytic hypochromic individuals. Thus, it contributes to reducing the spread of genetic diseases.