Migratory History of Populations and its Use in Determining Research Direction for Retinal Degenerative Disorders

Abstract

South Africa represents an anthropological and geographical cul de sac to which several ancient African populations have migrated from Central, East and West Africa. This subcontinent may thus represent access to some of the most ancient homo sapiens genetic material that is still in the process of being passed from one generation to the next. The indigenous African subpopulations may also carry some of the most ancient (non-lethal) disease-causing mutations. Apart from this interesting niche for the study of inherited disorders, this subcontinent has also attracted waves of immigrations over the past 500 years. The first major European settlement was by Dutch seamen in the region of the Cape of Good Hope. This was followed by colonists from Germany and France and other parts of Europe, including a large contingent from Britain. From the East, immigrants also hailed from India and Malaysia. With regard to the potential of genetic investigations, there are significant numbers of communities that have remained as true as is possible to their ancestral lineages from their lands of origin. This has been reinforced by the sociopolitical practise of apartheid. The high degree of clinical and genetic heterogeneity in our cohort of research subjects with retinal degenerative disorders, coupled with the observation of certain disorders segregating in a manner which fits a ’land of origin’ scenario has led us to use the information of ancestral lineages to assist in deterring the strategy to defining the underlying genetic causes in RDDs.