DNA gives insight into southern Africa’s past
BRAAMFONTEIN - The extraction of ancient DNA from a mummified man tells of life in southern Africa, 300 years ago.
Wits University can now boast being apart of the first successful extraction of ancient DNA from a southern African mummy, the first individual found in northern Botswana, in the Tuli block and is estimated to be around 300 years old.
The remains were those of a man of African origin. He was interred in a tightly flexed position, wrapped in an animal skin that was tied with a plant fibre rope.
Professor Maryna Steyn, head of the School of Anatomical Sciences, together with researchers from the University of Zurich in Switzerland, the University of Pretoria and the University of Botswana have published these findings in a paper called Radiological and genetic analysis of a late iron age mummy from the Tuli Block, Botswana, in the South African Journal of Science . Steyn coordinated the project from start and still continued to do so once she moved to Wits from the University of Pretoria last year.
The actual ancient DNA (aDNA) extraction was done in a dedicated laboratory for DNA extraction in Zurich about two years ago. Then the researchers worked on and submitted the paper on their findings.
Besides the DNA extraction, the researchers have presented one of the first computerised tomography (CT) scans of a mummified individual from southern Africa. The scan revealed none of the internal organs were preserved. The skeleton was intact apart from degenerative changes in the lower vertebrae of the spinal column, which suggests an age of over 50 but the cause of death is still unknown as there are no signs of injury.
Mummified human remains are valuable sources of information on past populations. The analysis confirmed the individual had similar genetics to a Sotho-Tswana or Khoisan, which is expected from the region. “We know that some genetic interchange occurred between the Khoisan and Sotho-Tswana. So in a sense it is what we expected, but it is nice to have it confirmed nevertheless,” said Steyn.
The team also took other samples that could be used for further analysis, for example, for isotope analysis, hair analysis, and analysis of diet.
Steyn added, “It was a privilege to work on these remains as they are rare. It tells us about population relationships, burial practices and health among others. So very valuable, and I also enjoyed the contacts we made with various researchers in Switzerland.”
Details: Wits University, 011 717 1000.
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