AN Australian research team including international scientists has published findings that reinterpret the history of early Aboriginal descendants.
Published this week in Science, the researchers from Murdoch University, UWA, Griffith University and the University of Copenhagen, used a 100-year-old lock of hair donated by an Aboriginal man to map the man’s DNA.
Scientists used 0.6 g of hair for DNA extraction and although the sample was 100 years old, the genomic sequence showed a high degree of fragmentation (average length 69 base pairs). The genome was sequenced to an overall depth of 6.4×; roughly 60 per cent of the genomic regions covered were sequenced to an average depth of 11×.
By studying the DNA, the researchers have discovered that modern Aboriginal Australians descend directly from an early human migration into Asia that took place approximately 70,000 years ago.
The results suggest that modern day Aboriginal Australians are direct descendents of the first people who arrived in Australia about 50,000 years ago.
Murdoch University’s Dr Michael Bunce, an expert in ancient DNA, says the findings have helped unlock how early humans moved around the globe.
“It really is remarkable the recent advances in technology. The information encoded in DNA can tell us a lot about how humans explored the globe,” he says.
The DNA from the lock of hair, which was donated to a British anthropologist by an Aboriginal man, has revealed insights into how the first humans scattered across the globe.
Researchers also found significantly larger proportions of shared derived alleles between the Aboriginal Australian and Asians (Cambodian, Japanese, Han, and Dai) than between the Aboriginal Australian and Europeans (French).
The DNA showed no genetic input from modern European Australians, which suggests that ancestors of Aboriginals moved away from the ancestors of other human populations in Africa between 64,000 and 75,000 years ago.
They also represent the oldest continuous population outside of sub-Saharan Africa.
According to the lead scientist Professor Eske Willerslev from the University of Copenhagen, ancestral Aboriginal Australians were the first human explorers.
This research, which was endorsed by the Goldfields Land and Sea Council, an organisation which represents the Aboriginal traditional owners for the region, shows that Aboriginal Australians have the longest connection with the land on which they live today.
Previously, the widely accepted theory was that all modern humans came from a single African migration into Asia, Europe and Australia.
In this theory, the first Australians split from an Asian population which had already separated from the earliest ancestors of Europeans.
The implications for the new findings are profound in understanding how our human ancestors moved across the globe.
Reference Publication: An Aboriginal Australian Genome Reveals Separate Human Dispersals into Asia. Morten Rasmussen et al, Science Published Online September 22 2011. DOI: 10.1126/science.1211177