Testing Scotland's DNA: Who do you think you are?

It arrived in a small cardboard box, no larger than a few packs of playing cards laid side-by-side. A rather theatrical promise on the outer flap: ‘These are the stories only DNA can tell’. Upon opening, I found a neat set of instructions, a return postage label and a plastic tube to spit in. My adventure with ScotlandsDNA had begun.

Based in the Scottish town of Melrose, ScotlandsDNA started in November 2011 with one simple aim: to allow people to carry out the ultimate family tree. With their sights set far beyond a mere generation or two, ScotlandsDNA uses state-of-the-art genetic technology to examine various markers in their customers’ DNA, tracing their ancestral lineage back through millennia. A small company, their website gives the impression of a rather close knit group of researchers and managers, and in a nice touch displays each staff member’s chromosomal info in their biography.

Since opening their doors nearly four years ago, over 10,000 people have mailed in their saliva for testing. It’s a fairly impressive number considering the arguably high asking price (around £200 per person). Outside the individual information, however, this ever-growing sample size allows for further research, with each customer able to anonymously add their DNA results to the company’s database. The hope here is to learn more about the genetic history of Scotland, and of the British Isles as a whole. The larger this collection, the easier it becomes to spot patterns in the distribution of certain genetic markers. Put simply, this could help map out how, when and where the population of the UK was formed over the past few thousand years.

So how exactly does the tech work? According to Katie Barnes (geneticist, carries a copy of the red-head variant Arg163Gln on chromosome 16) it begins with life itself – fertilisation. “All the letters in our DNA have to be copied for the new generation into sperm and eggs,” she explains. “And sometimes a mistake is made, a T is added instead of an A, for instance.”

She’s talking about our genetic code. Four letters, A, C, G and T – the initials of the nucleotides adenine, cytosine, guanine and thymine. Together, these molecules make up our DNA, and can be read like a string of characters on a page. Nonsensical to you and me, but show it to a geneticist and they may be able to spot certain patterns, including the all-important copying errors. “These changes in the DNA code will be inherited by that person’s descendants, and are called markers,” Katie continues. “The vast majority of our DNA has no known function, it’s just being carried as ‘junk’, and it is here that most of the DNA markers are located.”

Using these distinctive markers – passed down through generations upon generations – researchers working with ScotlandsDNA are able to trace a person’s genetic lineage right back to the point where the error occurred. Often this is over hundreds of miles and thousands of years away from where the person is now, and gives a fascinating insight into where their ancestors originally came from.

"Since opening their doors nearly four years ago, over 10,000 people have mailed in their saliva to ScotlandsDNA for testing"

The process also differs depending on your sex. For males, it’s all about the Y chromosome – a chunk of genetic material that helps determine your gender, and one females lack. It therefore stands to reason that tracing back any DNA markers present on the Y chromosome would throw up a genetic lineage specific to that person’s fatherline. Using custom-built technology, ScotlandsDNA are able to read over 15,000 markers on this chromosome alone.

As for the females of the species, the company targets something a little bit different: mitochondrial DNA. This is DNA found in our mitochondria cells. Think of them as power converters; they transform the chemical energy from our food into a material the rest of our cells can use. Mitochondrial DNA is passed down to both sexes by – you guessed it – our mothers, meaning researchers are able to look back along a person’s motherline by following the unique markers found inside. For geneticists, this throws up over 3,000 markers to track, and ScotlandsDNA tracks them all.

Combining the above technologies with an additional 200,000 markers found scattered throughout the rest of our genetic code allows for an incredibly detailed map to be created for each individual – especially if you’re a man. Women (without the Y chromosome) can only track their motherline, although their brother or father could also take part to fill in the missing data.

Such a powerful tool is bound to throw up some interesting results from time to time – and Katie is quick to agree. “Usually people will find something surprising about their DNA,” she explains. “One of the most exciting things about tracing your ancient history is that it has the potential to reveal something about your past that you couldn’t have known without taking a DNA test. For example, we had one customer from Caithness who discovered his motherline was a specific African lineage that hadn’t been found before in Western Europe. After tracing his family history, he confirmed that it had arrived in Britain through the slave trade.”

It all sounds very exciting, peeking back a few thousand years to see where you really came from – and possibly even how you got here – but how does the process work in practice? Luckily this was something I was able to try first hand, as ScotlandsDNA provided me with a kit to test out.

The process is incredibly simple. Thanks to our DNA being present in nearly every cell, all that’s required is a sample of your saliva. Fill up the plastic tube provided, add the preservative, slap on the return postage label and pop the box back in the mail. I had the whole thing done before my morning porridge was out the microwave. The results take a bit of time, and in my instance, nearly five months – but hey, you can’t rush science. Besides, what eventually dropped through my letterbox was definitely worth the wait!

Two large booklets set out my father and motherline in surprising detail. My male ancestors are Indo-Iranian, apparently, with the markers on my Y chromosome arising around 5,000 years ago in Eastern Europe. I share my DNA group with many males in Kyrgyzstan, as well as with those living south of the Himalayas. In Britain and Ireland it’s rare –€“ found in less than 0.4% of the male population. My motherline, on the other hand, were classed as Foragers; women who lived in extended family bands that gathered a wild harvest of edible plants and eggs, as well as hunting small animals and birds. Arising a whopping 27,000 years ago in Western Asia, my female ancestors moved through Iraq, Syria and North Africa to end up in small numbers here in Britain and Ireland.

It’s incredibly interesting reading to say the least. And beyond the personalised data, both booklets offer a wealth of info on the science behind it, as well as what the Earth was like for my ancestors, how they lived and what conditions may have arisen to drive them across continents. A third booklet, called All My Ancestry, gives a breakdown of each of my chromosomes and hints at where in the world they came from. It shows a wonderful picture of how interconnected we all are, and how scattered our genes become the further back you look.

Rounding out the results are a couple of intriguing bits of information on eye colour and red hair (or in Scotland, the ever-present ginger gene). They outline how common various eye colours are, what colour of eyes my children might have and why blue eyes became so common across Europe (it’s all to do with sexual selection, apparently, like a peacock’s tail). Oh, and my MC1R gene is free of ginger, meaning I won’t be able to pass red hair onto any future kids.

All in all, then, it’s a resounding success. The price point might seem high at first, but the technology behind it is clearly cutting edge and the wealth of data you get back is genuinely fascinating. From individual info on where your family comes from and how they lived, to stats on hair and eye colour – they even offer an add-on that checks for male-pattern baldness. Opening up the realm of genetic lineage to the public is still fairly new, but as time passes and more people take part, they bring with them the potential to turn back the clock on how mankind spread across the globe. By utilising a process that’s both unique and universal in equal measure, perhaps that promise on the side of the box isn’t quite so theatrical after all.