The Malagasy people of Madagascar carry the genes from ancestors in both nearby East Africa and also distant Borneo suggesting a big migration from Asia back to Africa 2,000 year ago, British researchers reported on Tuesday.
The genetic study supports the puzzling finding that the Malagasy language more closely resembles Indonesian dialects than east African tongues but does little to answer the question of how the settlers arrived.
Madagascar, the largest island in the Indian Ocean, lies 250 miles off the coast of Africa and is 4,000 miles from Indonesia.
Its long isolation has led to the evolution of unique animals, including lemurs, rare birds and plants.
A team of genetics experts at the universities of Cambridge, Oxford and Leicester looked at both the Y chromosomes of Madagascar residents, inherited virtually unchanged from father to son, and the mitochondrial DNA, passed directly from mothers to their children.
Tiny mutations in these two forms of DNA provide a kind of genetic clock that can help scientists trace human migration and inheritance.
The results showed clear similarities to sequences found on the island of Borneo, now shared by Indonesia, Malaysia and Brunei.
"The origins of the language spoken in Madagascar, Malagasy, suggested Indonesian connections, because its closest relative is the Maanyan language, spoken in southern Borneo," said Matthew Hurles, of the Wellcome Trust Sanger Institute at Cambridge, who helped lead the study.
"Malagasy peoples are a roughly 50:50 mix of two ancestral groups: Indonesians and East Africans. It is important to realize that these lineages have intermingled over intervening centuries since settlement, so modern Malagasy have ancestry in both Indonesia and Africa."
The findings suggest a substantial migration from southeast Asia between 1,500 and 2,000 years ago, the researchers report in the American Journal of Human Genetics.
Tue May 3, 2005 04:45 PM ET - WASHINGTON (Reuters)
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