In this study, molecular and genetic analysis of ? -thalassemia minor in a sample of Baghdad population were made. The study included hemato- logical screening of peripheral blood cells, pedigree analysis for carriers s' families and their relatives, hemoglobin electrophoresis, and molecular analysis of ? -globin gene, all in comparison with normal people. The first part included hematological prescreening for 100 carrier of ? -thalassemia minor attending Central Health Public Laboratories came from Baghdad. The hematological tests were packed cell volume (PCV), mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH). Results obtained showed that PCV was 32 -38 % for carriers, MCV was 62 -65 fl for carriers, and MCH was 19 -26 pg for carriers. Moreover, hemoglobins A, A2, F were also determined using electro- phoresis that showed, carriers had elevated levels of HbA2 and decreased levels of HbA in comparison with normal people. In addition, it was found that there is a morphological change of the red blood cells (RBCs), since RBCs took abnormal shapes due to the disease. The white blood cells were at normal levels in carriers. This part of the study included also, hemoglobin analysis of carrier parents and their affected children with ? -thalassemia syndrome. Three electrophoresis techniques were used and results obtained showed that there is a remarkable difference in hemoglobin electrophoresis among carriers who represented blood samples taken to complete this study. Results showed that there is also a remarkable difference in hemoglobin electrophoresis in carriers and patients, in comparison with normal people. The pedigree analysis of families with ? -thalassemia syndrome was made depending on data obtained previously and family history. The analysis showed the transfer of the trait among generations, especially in families preferring marriage of relatives. The second part of this study included the molecular analysis at DNA level for Baghdad families with ? -thalassemia, using four specific primers for the PCR amplification and specific enzyme for the restriction analysis. The results showed the presence of frameshift mutation in codon 6 of the ? -globin gene in carriers with thalassemia minor (heterozygous) that led to partial depression in gene expression in ? -globin gene in comparison with normal people since it occurred in one allele of the gene, which led to the presence of single DNA band after electrophoresis, while results of the normal individuals showed the presence of two DNA bands on the gel, indicating the presence of the restriction site and no changes in the gene expression occurred. This is the first study concerning the molecular level and mutation type in Baghdad to be compared with the other parts of Iraq and with the neighboring Arab Countries.
