IT is well-known that all thoroughbred horses are descended in the male line from one of three Arab stallions brought into England between 1687 and 1729: the Darley Arabian, the Byerley Turk and the Godolphin Arabian.
The British: A Genetic Journey
by Alistair Moffat
Birlinn, 272pp, £17.99
Actually 174 Arab stallions were imported in the 18th century, but the direct line of male descent has not survived except in the case of these three, though the bloodline of many of the other stallions appears on the dam side of pedigrees. None of this is directly relevant to Alistair Moffat’s fascinating study of our DNA inheritance yet it might usefully be borne in mind because establishment of an individual’s DNA, traced back for centuries, does persuade us to favour one line of our ancestry above other ones. If you are told, for instance, that your DNA indicates that you have Pictish or Viking gene, you may be inclined to forget just how varied your ancestry actually is. But a simple calculation makes this clear. Your number of direct forebears doubles every generation. Go back 12 generations and there are 4,096 of them. Yet 12 generations take us back less than 400 years. We have, in other words, an awful lot of ancestors.
Actually of course we’re all related to each other, first by way of “Mitochondrial Eve” who “is now thought to have lived approximately 180,000 years ago in East Africa” and then through “Adam”, the ancestor of all men. However, Moffat writes that it is a misconception “to suppose that this Eve and this Adam were the only man and woman living at these times”. They never met; indeed Adam appeared some 40,000 years after Eve. It is just that “theirs are the only lineages that survive in the male and female lines, while others have died out” just like the male-line lineages of 171 Arab stallions in the stud book.
DNA tests often establish what common sense has suggested. Invasions and conquests don’t necessarily result in the massacre or exile of the defeated. What, for instance, happened to the Picts who mysteriously disappear from the history books? The answer, Moffat suggests, is “not a lot”. They stayed where they were. “Some 17 per cent of men in Central Scotland (Angus and Perthshire predominantly) have a Y-chromosome marker identified as characteristically Pictish.”
George Mackay Brown once remarked to me, rather sadly, that there “wasn’t a lot of Norse blood in Orkney now”. He may have been too pessimistic. According to Moffat, “in Orkney, 20 per cent of the modern male population carry the classic Y-chromosome marker of M17, and amongst those with older surnames such as Clouston, Rendall, Isbister or Flett, the proportion rises to 35 per cent.” Nevertheless they are a minority, more Orcadians tracing descent also from immigrants after Orkney was incorporated into Scotland.
Royal bloodlines are, like those of throroughbred racehorses, better documented than most. Moffat is happy to reveal that Princes William and Harry have “inherited a small proportion of Indian DNA” from one Eliza Kewark, the concubine, perhaps wife, of an Aberdeenshire merchant in the East India Company, Theodore Forbes. Their daughter married James Crombie from Aberdeen (“makers of the famous Crombie cloth”), and their great-granddaughter Ruth was Princess Diana’s maternal grandmother.
If we could reliably go back far enough we would probably find that vast numbers of us can claim some royal connection. In his biography of Edward III, the historian Ian Mortimer claimed that 90 per cent of English people are descended from that king. Perhaps a comparable number of us Scots stem from Robert II, the first Stewart king, who had at least 15 children from his two marriages, and also 19 known illegitimate ones. One should remember that daughters of mediaeval kings tend to disappear from history rather quickly.
A lot of the science in this book is less than Greek to me. Nevertheless, even those for whom chromo somes or DNA markers are baffling will find the book fascinating. Moffat has always been a magpie historian, picking up unsuspected jewels of information, at the same time never afraid to speculate, often in anagreeably provocative manner.