PpigScience: DNa

Reconstruction of Cheddar Man, so named for his discovery in Somerset's Cheddar Gorge in 1903

Groundbreaking DNA research has shone new light on the early origins of Britain's early settlers, reconstructing in unprecedented detail the face of Cheddar Man, the nation's oldest near-complete skeleton. The research reveals he had much darker features than was previously assumed, which has implications for our understanding of how lighter pigmentation spread through Europe.
Previous reconstructions of Cheddar Man, so named for his discovery in Somerset's Cheddar Gorge in 1903, weren't based on DNA data and painted a Mesolithic man with a lighter skin tone. He lived around 10,000 years ago, after his hunting and gathering ancestors migrated to Europe at the end of the last Ice Age, a time when Britain was attached to continental Europe.
"Until recently it was always assumed that humans quickly adapted to have paler skin after entering Europe about 45,000 years ago," says Dr Tom Booth from Britain's Natural History Museum. "Pale skin is better at absorbing UV light and helps humans avoid vitamin D deficiency in climates with less sunlight."
But using newly available DNA analysis, scientists from University College London (UCL) and the Natural History Museum have found that Cheddar Man actually has genetic markers usually associated with sub-Saharan Africa. The team drilled a 2 mm hole into his skull to gather bone powder from the petrous bone, the densest bone in the human body and therefore especially good at safeguarding the ancient DNA.
The process that followed made Cheddar Man the oldest British individual to have their genome sequenced. That information was then passed on to reconstruction specialists, who measured up the skeleton, scanned the skull and 3D printed a base for the model.

The skull of Cheddar Man, the oldest near-complete skeleton in Britain

"Of course facial reconstruction is part art and part science," says Booth. "But there are some standards of how thick the tissue is in different regions of people's faces so they can use those conventions to develop the morphology of the face."
The blue eyes, dark curly hair and darker skin pigmentation of Cheddar Man suggests that the lighter pigmentation associated with Northern Europe came to be far more recently than previously thought. The portrait painted by the scientists is similar to that of several other Mesolithic skeletons to have their DNA analyzed around Europe.
"Cheddar Man's genetic profile places him with several other Mesolithic-era Europeans from Spain, Hungary and Luxembourg whose DNA has already been analyzed," UCL's Professor Thomas explains. "These 'Western Hunter-Gatherer's' migrated into Europe at the end of the last Ice Age and the group included Cheddar Man's ancestors."
The researchers say that today, around 10 percent of British indigenous ancestry can be linked to that population.

Source: University College London, Natural History Museum,NewAtlas

Scientists have recently, for the first time, extracted full nuclear genome data from ancient Egyptian mummies(Credit: bpk/Aegyptisches Museum und Papyrussammlung, SMB/Sandra Steiss)

For the first time, scientists have extracted full nuclear genome data from ancient Egyptian mummies. The results offer exciting insights into how different ancient civilizations intermingled and also establishes a breakthrough precedent in our ability to study ancient DNA.
The international team of scientists, led by researchers from the University of Tuebingen and the Max Planck Institute for the Science of Human History in Jena, sampled 151 mummified remains from a site called Abusir el-Meleq in Middle Egypt along the Nile River. The samples dated from 1400 BCE to 400 CE and were subjected to a new high-throughput DNA sequencing technique that allowed the team to successfully recover full genome-wide datasets from three individuals and mitochondria genomes from 90 individuals.
"We wanted to test if the conquest of Alexander the Great and other foreign powers has left a genetic imprint on the ancient Egyptian population," explains one of the lead authors of the study, Verena Schuenemann.

The area in Middle Egypt the researchers found their samples(Credit: Graphic: Annette Guenzel. Credit: Nature Communications, DOI: 10.1038/NCOMMS15694)

In 332 BCE, for example, Alexander the Great and his army tore through Egypt. Interestingly the team found no genetic trace of not only Alexander the Great's heritage, but of any foreign power that came through Egypt in the 1,300-year timespan studied.
"The genetics of the Abusir el-Meleq community did not undergo any major shifts during the 1,300 year timespan we studied," says Wolfgang Haak, group leader at the Max Planck Institute, "suggesting that the population remained genetically relatively unaffected by foreign conquest and rule."
They found that ancient Egyptians were closely related to Anatolian and Neolithic European populations, as well showing strong genetic traces from the Levant areas in the near east (Turkey, Lebanon).

One of the samples the researchers obtained DNA information from(Credit: Johannes Krause)

This genetic ancestry stands apart from more modern Egyptians who share around 8 percent of their DNA with Sub-Saharan African populations. The data offers a fascinating insight into a prolonged period where ancient Egyptian ancestry did not mix with its southern African counterparts. It also suggests that this gene flow into modern Egyptian populations occurred relatively recently, within the past 1,500 years.
The study points out that the Trans-Saharan slave trade, which moved an estimated 7 million sub-Saharan slaves up to Northern Africa, over a thousand years up to the nineteenth century, most likely was how this genetic line influenced modern Egyptians.
Now that a robust and reliable way has been developed to study the DNA of ancient remains the researchers hope to broaden their analysis across a wider geographical variety of mummies. This will not only help paint a clearer portrait of Egypt's population history but give us a greater understanding of the genetic movements of ancient civilizations in the region.
The study was published in the journal Nature Communications.

Source: Max Planck Institute for the Science of Human History, NewAtlas