Hemoglobinopathies (HbP) are recessive hereditary disorders of hemoglobin, characterized by microcytic hypochromic anemia. HbP diagnostics encompasses three specialties: hematological, biochemical... Show moreHemoglobinopathies (HbP) are recessive hereditary disorders of hemoglobin, characterized by microcytic hypochromic anemia. HbP diagnostics encompasses three specialties: hematological, biochemical and molecular testing. Results of all tests together form the complete diagnosis. The main objective of this thesis was to improve post- and prenatal diagnostics of the hemoglobinopathies. Several molecular assays have been designed, tested and validated. In addition, a number of informative hemoglobinopathy cases have been studied in detail. Diagnostics for hemoglobinopathies is strongly improved over the recent years. In particular the implementation of the MLPA technique made it possible to detect deletions and duplications in the globin gene clusters in patients who remain undiagnosed by applying the conventional techniques. The aCGH technology was developed in order to characterize the breakpoints of novel deletions detected by MLPA more precisely. This has led to the design of several relatively simple gap-PCR assays, which are useful in laboratories where MLPA and aCGH is not available. In addition, gap-PCR can be used for quick screening for the more locally occurring deletions or in family studies. A non-invasive prenatal diagnosis assay for hemoglobinopathies was developed by combining the PAP and MCA techniques. This method will be implemented in the current flow for prenatal diagnosis and will eventually make 50% of the invasive procedures redundant. Show less
The research presented in this thesis provides several novel insights regarding the _-thalassemia intermedia phenotype. Earlier studies observed that patients with _-thalassemia intermedia... Show moreThe research presented in this thesis provides several novel insights regarding the _-thalassemia intermedia phenotype. Earlier studies observed that patients with _-thalassemia intermedia experience a clinical complications profile that is different from that in patients with _-thalassemia major; which was primarily attributed to their transfusion-independence. In this work, a variety of clinical morbidities were explored and their associations with the underlying disease pathophysiology and risk factors were examined. The morbidities evaluated throughout the studies involved several organs and organ systems including the vasculature (venous thrombosis, pulmonary artery hypertension, cerebrovascular disease, and leg ulcers), heart, liver, kidney, endocrine glands (diabetes mellitus, hypothyroidism, and hypogonadism), bone (osteoporosis), and the hematopoietic system (extramedullary hematopoietic tumors). Findi ngs confirm that _-thalassemia intermedia should no longer be regarded as a mild form of thalassemia as patients experience serious manifestations involving almost every organ system. Show less