Genetic Diversity in Africa

Abstract

Africa exhibits a high level of human genetic variation, the origin of which is still not fully understood. However, the results brought by the study of several independent genetic polymorphisms in relation to other disciplines indicate that this continent has undergone major population movements possibly linked to the diffusion of the main linguistic phyla.

Keywords: human genetic diversity; Africa; classical polymorphisms; mtDNA; Y‐chromosome; GM

Figure 1.

Genetic relationships between 68 African populations analysed for the GM polymorphism of human immunoglobulins. The plot is a multidimensional scaling (MDS) analysis. (a) Different markers are used for distinct geographic regions: besides the obvious division of the African continent into its northern, eastern, western and southern parts, a fifth geographic region (Central‐West) was defined that includes populations from the countries surrounding the Gulf of Guinea, and that extends into the Central African Republic (CAR) to the East and into Angola to the South. (b) Different markers are used for distinct linguistic families.

Figure 2.

Genetic relationships between 40 African populations analysed for Y‐chromosome haplogroups. The plot is an MDS analysis performed on Wood et al.'s data. (a) Different markers are used for distinct geographic regions: the geographic regions are defined as in Wood et al. and as in Figure . (b) Different markers are used for distinct linguistic families.

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Further Reading

Bellwood P (2005) First Farmers, the Origins of Agricultural Societies. Oxford/Malden, MA: Blackwell Publishing.

Blench RM (2006) Archaeology, Language and the African Past. Lanham: Altamira press.

Blench R, Ross M and Sanchez‐Mazas A (in press) Methodological issues: linking genetic, linguistic and archaeological evidence. In: Sanchez‐Mazas A, Blench R, Ross M, Peiros I and Lin M (eds) Past Human Migrations in East Asia: Matching Archaeology, Linguistics and Genetics. London: Routledge.

Cavalli‐Sforza LL (1986) African Pygmies. Orlando: Academic Press.

Jobling MA, Hurles ME and Tyler‐Smith C (2004) Human Evolutionary Genetics: Origins, Peoples & Disease. New York, Abingdon: Garland Publishing.

Ruhlen M (1987) A Guide to the World's Languages. V.1, Classification. London: Edward Arnold.

Sanchez‐Mazas A (2001) African diversity from the HLA point of view: influence of genetic drift, geography, linguistics, and natural selection. Human Immunology 62: 937–948.

Tishkoff SA and Gonder MK (2007) Human origins within and out of Africa. In: Crawford MH (ed.) Anthropological Genetics: Theory, Methods and Applications. Cambridge: Cambridge University Press.

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Sanchez‐Mazas, Alicia, and Poloni, Estella S(Jul 2008) Genetic Diversity in Africa. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0020800]