Hemoglobinopathies: a longitudinal study over four decades.

Hemoglobinopathies are among the most common hereditary diseases of the world’s population. About 4.5% of all human beings carry a gene for a thalassemia or hemoglobin anomaly (1– 3, e6). The areas in which such abnormalities were originally most common extend from Africa over the Mediterranean basin and the Near and Middle East to Southeast Asia and the Indian subcontinent. Global migration in the modern period has led to a continual spread of these anomalies to all regions of the world, with the result that they are rapidly becoming more common in the industrialized regions of Northern and Central Europe as well (4, 5, 7– 12, e6). Amid the changing, multiethnic population of today’s Germany, there are 15 million persons with an immigrant background (13). More than 9 million of the immigrants now living in Germany come from risk countries for hemoglobinopathies (as defined by the relevant WHO criteria), in which the prevalence of heterozygous carriers ranges from 5% to over 30%, depending on the region (1, 3). It follows from a simple calculation, therefore, that perhaps 400 000 persons now living in Germany carry hemoglobinopathy genes. No precise epidemiological data are available at present, because there have been no systematic studies to count the number of carriers or patients with overt disease. The diseases arising from a disturbance in the formation of hemoglobin (Hb) are divided into two categories: Thalassemias Hemoglobinopathies in the narrower sense, i.e., hemoglobin structural variants: these are commonly designated Hb anomalies (4, 16, 17). Physicians in Germany have devoted an increasing amount of attention to Hb anomaly diseases in recent years and have found them to be an important issue in patient care. It is thus useful for clinicians to have an overview, complete with numerical data, concerning the occurrence, spectrum, and geographical distribution of Hb defects.