Thursday 25 April 2019

DNA blueprint of the Irish revealed

Damian Corless

'You won't find a gene that makes the Irish fond of drink, any more than you'll find a gene that makes the Irish especially prone to buying property at grossly over-inflated prices."

That is the sage scientific advice of Professor Brendan Loftus, head of the UCD research team which this week revealed it has mapped the complete genetic code of an Irish person for the first time.

The entire DNA blueprint for a human being was first published in 2003 in the US, but there are six billion people on earth paddling about in many localised gene pools and the island of Ireland is a locality with its own unique genetic scenery. The UCD team has, quite literally, put us on the world map.

But back to the relation between DNA and the demon drink. It has been a matter of record for millennia that a high proportion of Chinese, Japanese and other East Asian peoples can't handle their drink. Just a couple of units can cause falling-down drunkenness and a skin-blotching condition popularly known as 'Asian Flush' or 'Asian Glow' which, in extreme cases, can bring the entire body out in an unsightly rash.

Modern science has shown that this ancient alcohol intolerance is caused by a misfiring gene that can't encode a key enzyme. On a more sinister note, it has also been found that anyone missing the enzyme who drinks even two pints a day ramps up certain cancer risks tenfold.

Although genome research is racing ahead, it is still in its infancy. The existing DNA databank cannot explain Ireland's destructive love affair with drink nor the hidden currents of the Fianna Fail gene pool, but it can help tell us where we've come from and hopefully provide us with safer directions as to where we're going.

Now that it has been sequenced, the Irish genome can be studied by medical science in an attempt to define what makes Irish people susceptible to some disorders and not to others. The possibilities for prevention and cure are enormous, but at this early stage no one is quite sure what advances will emerge from this bulging cache of new information. Our lesson from the mobile phone revolution, where texting grew from a mere afterthought to sweep the world, is that we should expect the unexpected.

With DNA research right now, as with life in general, it appears that hindsight comes closest to providing us with 20/20 vision. As Prof Loftus puts it: "Your genome contains your history, your geography, your society, your family."

Ireland's geography has had a huge part to play in shaping the nature of our society and our closest family ties. According to Loftus: "The geographic isolation of Ireland over generations would affect the size of the gene pool by limiting the type and number of potential mating partners."

Major genetic surveys of Ireland and Britain have established that the gene pool of both islands is amongst the least diluted in Europe. The genetic evidence shows that three quarters of the ancestors of the Irish and British people were the pioneering settlers who arrived at the end of the last ice age between 17,000 and 8,000 years ago. The inescapable upshot of this is that the Irish are not Celts, any more than the English are Anglo-Saxons.

In fact, both the Irish and the British are Basques, with the Irish significantly more Basque than our neighbours across the pond, who've absorbed more migrations from Europe over the centuries.

Scientists estimate that Ireland's gene pool has changed remarkably little since the first hunter-gatherers from Iberia followed the retreating ice cap, beachcombing northwards and settling this newly exposed and empty land. The dilution rate for Ireland is estimated at a tiny 12%, against 20% for Wales and Cornwall, 30% for Scotland and 33% for England.

The genetics suggest that, with sea levels low, the Basques simply walked to Ireland, becoming cut off generations later when rising seas created the island we know. Ancient Irish legends say that there were six invasions or migrations from the south many generations before the Celts arrived around 300BC.

The evidence suggests that the Celtic language, fashions and technologies which are supposed to define our Irish heritage, were acquired as cultural accessories in the way that today's Irish schoolkids flounce about under the impression that they're gangsta rappers straight out of Compton or Beverly Hills brat-packers.

The Irish and Basques share by far the highest incidence of the R1b gene in Europe, which has a frequency of over 90% in Basque country and almost 100% along parts of Ireland's western seaboard.

If further proof were needed, there's the physical fact that the Basques are distinguished by a very high incidence of fair (and some reddish) hair, pale skin, blue eyes, and, apparently, sticky-out ears. Sound like anyone you know?

But for every badge of Irishness we can now firmly blame on our genes, others have been stuck on us by disapproving foreigners. The oddest, which crops up repeatedly in accounts of early travellers, is that "plebian Irish females" have "the thickest ankles in the world". The English writer Francis Grose claimed in the 1700s that "Irish women wear the thick end of their legs downwards".

Even Dean Swift, who wrote A Modest Proposal attacking England's treatment of the Irish, believed that the native Catholics were genetically lazy, drunken and thick, describing them as "our savages".

With friends like that . . .

Irish Independent

Today's news headlines, directly to your inbox every morning.

Don't Miss