Edinburgh genes show pioneer spirit

For almost three years ScotlandsDNA has been analysing the ancient ancestry of the people of south-east Scotland and some fascinating results have emerged.

First, here’s how it works. All of us inherit six billion letters of DNA from our parents, roughly three billion each from mum and dad.

Men pass on the Y chromosome to their sons and mums give mitochondrial DNA to all of their children and it is through these small pieces of DNA that we can trace our ancestry, our fatherlines and motherlines.

This amazing genetic journey is made possible by  markers. These are little mistakes of copying as the six billion letters of DNA are passed down the generations and they make it possible to tell where our ancestors came from and also how old our ancestry is.

The markers found in the people of Edinburgh and the south-east of Scotland have a great story to tell, a story only DNA could tell.

About 11,000 years ago the world was ice. Much of the northern hemisphere and all of Scotland lay sleeping. Nothing and no-one could survive in this brilliant white landscape. When the ice began to melt, plants grew, animals returned and small bands of pioneers came north. Around the Capital they left traces of what their lives were like.

Hunter-gatherers camped near the shore at Cramond and archaeologists have found the holes where they rammed rods of whippy green wood into the earth.

These were lashed together to make the framework of a bender tent, its covering likely to have been hides of animals brought down or trapped.

Probably only a few centuries after the camp was pitched at Cramond, a family of pioneers built what is probably the oldest house found in Scotland.

In the summer of 2012, the earth-moving machines working on the southern approaches to the new Queensferry Crossing across the Forth came across postholes in a field near the village of Echline.

Shaped like a chunky tepee with thick posts or tree-trunks canted inwards to form a cone, the house dated to 8240BC.

Covered with turf, bracken and perhaps hides, it had more than one hearth and was probably snug enough as the chill winter winds blew in off the firth.

But who were these people who sat around the circle of firelight? They were amongst the first to come north to hunt and gather the wild harvest or roots, fruits, berries, fungi and birds’ eggs over the landscape of what is now western Edinburgh – but where did they come from?

In the city and across the Lothians and Borders, the most common mitochondrial DNA marker is that of the Pioneers, the people who trekked north after the ice melted.

Most came from what are known as the Western Ice Age Refuges, the caves in the limestone gorges on either side of the Pyrenees, far enough south to escape the worst of the polar climate.

The most famous cave is at Lascaux in the river valley of the Vezere, where its walls are covered with wonderful paintings of the fauna of the ice age – bison rumble across the plains, stags rear their heads, wild cattle fight and wild  horses gallop. The reason that so many descendants of the artists who made these startling images and the people who gazed at them are found in Edinburgh and the south-east of Scotland is a consequence of what is known as the wave effect, or gene surfing.

As the climate warmed, family bands moved north and left the familiar landscape of the Ice Age refuges, the ancestral DNA of those on the leading edge of the first wave of migrations multiplied faster than those behind them.

It may well be that these intrepid and resourceful people, those who first saw Edinburgh’s great rock and Arthur’s Seat, were especially hardy as they entered and settled in the empty landscape.

Their equally hardy children survived and multiplied. Almost a quarter, 24 per cent, of the population of Edinburgh and south-east Scotland carry the marker of the Pioneers. Part of the reason for this concentration is that the wave of migration could wash up no further than Scotland.

Edinburgh is truly the city of the Pioneers. It is the largest ancestral group in the south-east and their DNA leads back to the painted caves, the ice age refuges of the Pyrenees and the warmer south.

The darkness of our prehistory is further lit from the east. When the sun rose over the camp at Cramond and the tepee house at Echline, its rays shone not across the North Sea but across a huge, long-lost subcontinent.

Now drowned under the waves, the existence of what is known as Doggerland allowed our ancestors to walk from Europe to Scotland.

The weight of the ice on Scandinavia had forced the crust of the earth to rise to become dry land and it took millennia for Doggerland to sink below the sea. By 4000BC its last island (now the shallows of the Dogger Bank) was gone. But in the four or five millennia before then men walked across the great subcontinent to settle in south-east Scotland.

Their Y chromosome marker has been discovered. Labelled Saxon, it is common in Germany in ten per cent of men, but in Edinburgh, the Lothians and the Borders four per cent carry this remarkable genetic legacy.

Not all of them walked to Scotland because people continued to migrate from the east across the North Sea, but many did.

Hunter-gatherer populations were tiny by modern standards and perhaps fewer than a thousand people lived in Scotland in the ninth and eighth millennia BC. But these family bands had wide ranges where they harvested roots, fruits and berries, and gathered firewood. The people at Echline had neighbours. At East Barns, near Dunbar, the remains of a similar tepee house were found.

There was another down the Northumberland coast at Howick and it may be that these extraordinary structures were made by the descendants of people who had walked across Doggerland.

The ancestors of a substantial proportion of the people of Edinburgh arrived at the foot of the Castle Rock many thousands of years ago – and DNA analysis has shown that in all that long time large numbers have not strayed far, a remarkable continuity.

• Alistair Moffat is managing director of ScotlandsDNA. He ran the Festival Fringe from 1976 to 1981, went on to become an award-winning documentary maker, and is the author of many books about Scotland’s history.

ScotlandsDNA can be contacted at www.scotlandsdna.com or on 0845 450 2483

Doing detective work

Men inherit their motherline marker, what is known as mitochondrial DNA, but they cannot pass it on. Only mums can.

Ian Rankin inherited the T marker from his mum and it arose a long time ago in western Asia, in about 25,000BC. In an epic journey over many generations, his motherline ancestors trekked across thousands of miles to reach Scotland.

With nine per cent of men and women in Edinburgh, the Lothians and the Borders carrying this marker, it is surprisingly common and found in even higher percentages across other parts of Britain. But it is most common in Iraq, Syria and North Africa. Hidden inside our bodies are remarkable affinities with people who live thousands of miles away. No doubt Inspector Rebus will have discovered a link.