Inherited disorders in the black population of southern Africa. Part I. Historical and demographic background; genetic haematological conditions.

Genetic, geographic and socio-economic diversity has resulted in disparity in the relative prevalence of many inherited disorders and congenital conditions in the populations of southern Africa. In the first section of a 3-part article an account is given of the historical and demographic background in relation to factors which influence the presence and frequency of faulty genes in the black community. In addition, inherited haematological conditions--in particular haemoglobinopathies, red-cell enzyme and membrane defects--are discussed in terms of their clinical, genetic and anthropological significance. The conditions transmitted by simple genetic mechanisms are documented in Part II, with discussion of those notable for their unusually high or low prevalence. In the final section multifactorial, chromosomal and non-genetic congenital disorders are reviewed and a number of unusual conditions of obscure aetiology are mentioned. In this 3-part overview an attempt has been made to document present knowledge and to provide a bibliography for inherited and congenital disorders in the black population.