Sunday, 16 August 2009

DNA, Genes, And All That


DNA, GENES & ALL THAT

Essentially there are three types of DNA assessment available to the public. These are:

Y Chromosome tests, which define the male line from father to son. These are used for ancestral problem solving and paternity issues; for surname studies; and for a variety of kinship groupings, tribe (clan), caste, extended families, broad ancestry etc.

Mitochondrial DNA, that defines the female line from mother to daughter. These have been used to try to estimate population movements, in that the child-bearing females are critical in population expansion. At the earlier stage of DNA testing attempts were made to identify human groupings on this basis. When Y Chromosome testing became available it was found the patterns were not the same. The debate continues.

Autosomal DNA, that is a depth examination in the 22 chromosomes other than the Y to seek the pattern of overall sources of ancestry. At 12 generations back there is a total potential of 4096 ancestors at that point for any individual. Whilst the actual figure in each case may be lower, it may well still exceed 3000. Beyond twelve generations the increase continues, probably at a lower rate. For the great majority of people beyond the very limited numbers in enclosed or highly restricted groups this implies that the total of an individuals ancestry cannot be limited to one social class, geographical area, or kinship group. For those groups or people who know that their ancestry is widely based this can help them define the major elements. But the definitions are broad in scope, entail continental groupings, and cannot distinguish between the nation states and other political entities that historically are very recently contrived.

Phases of Interest

The classification of periods and the drawing of lines at different points of time is an intellectual minefield with several dangers. One is the risk of losing sight of the woods for the trees, and another that the scheme adopted may not follow the evidence but lead to a form of analytical rigidity with the effect that findings and evidence are forced into a set mould irrespective of what the reality may be, because for particular groups and structures it is necessary to have that theoretical basis for their status, work, or to retain the integrity of their belief systems.

So a key problem in this field is that too many people can jump to conclusions, suppose grand theories on findings that are really very limited in scope, or have fixed agendas to follow from the recent past in the interpretation of data. There are also the dangers of misunderstandings leading to more serious problems. In the UK we have had major legal fiascos arising from the manipulation, gross mishandling and misinterpretation of DNA and statistical data, and this in courts where one might expect the sharpest minds to be at work on the most expert and informed evidence available.

The phases I suggest are crude lines drawn to be able to distinguish potential areas of interest and nothing more, they are not a grand historical scheme, simply marks in the sands of time. The first phase is the period from around 1700 or 1800 to the present. This is to find lost branches of known families, or lost cousins in the movement of populations around the world. For some it will as a result of the many diaspora and flights from the land, and for others to identify from whence their families came. The second is broadly the period 1100-1800 the pre-modern economy, the time of surname formation, and of the recorded history of much of Europe. The third is the Post Roman to 1100 period where the recorded history is very limited, there is a great deal of myth and legend, all too often taken literally, and a story that is becoming more complicated and indefinite as archaeology reveals more of the past.

The fourth is the period of Roman Britain and the Ice Age where the written sources are very sketchy and of doubtful reliability, but again the archaeology is becoming more complex. The fifth is the Bronze Age where there are substantial settlements, but we rely heavily on what comes out of the ground. For much of this and the earlier times the same applies to a much greater degree. We then depend on archaeology, dendrochronology, the ice cores and the many and various means of scientific analysis. The sixth, seventh and eighth phases represent the Neolithic, the Mesolithic, and the Palaeolithic, where the size of settlements is reduced as we go further back in time, and farming gives way to hunting and gathering. Again we are leaning to be less dogmatic about these matters, it seems that later hunter gathers may have had means of cultivation, and the farmers did more hunting than we have assumed.

Phase One – 1700/1800 to Now

Who on Earth am I related to? A great many people may wish to know that, although human emotions being as they are, the answer may not be welcome. A fairly near cousin who is unknown may have left his DNA at the scene of the crime, and you may be obliged to answer questions about family history about which you are sadly unclear, but if a respected and famous person is found to be one of the family that might be a happy result. Also, where did all those cousins go, and who are they? Re-uniting families can be attempted. Historically, the collation of evidence on a larger scale may lead to clarification and re-assessments of what is believed to have happened in recent history. Some of the assumptions that are made about class, social, and personal mobility have to be questioned. One thing is certain, our DNA is not our own, nor is it our private possession, we share it with others, indeed all others.

Phase Two - 1100-1800

A number of similar considerations will apply to this period of history, although broader in the scope of enquiry, and taking account of greater complexities of movement, structure, and the patterns of relationships. This will go beyond families and considerations of existing national boundaries, many of which are historically quite recent in inception. One area is surnames.

If anyone wishes to have a surname group study it is possible, but does rely on enough people to be willing to give samples. Sometimes it suggests common close ancestry, and sometimes not. We have to be aware that surnames have come into use in Europe only in the last thirty or fewer generations, and that the fixing of those names and spelling can be recent, for example Saxe-Coburg-Gotha and Battenberg’s becoming Windsor’s in 1917, despite the protests of the holder of that ancient title. If the findings suggest a common pattern amongst a large enough proportion of the sample, this could point to a degree of relationship, and perhaps nature of distant origin in broad terms.

What it might be in detail is another matter. If many Macdonald’s seem to have common male origins, this does not mean that the “Somerled” gene has been found. We do not have his DNA, and too many questions arise. One is that we cannot be sure where the early males who left most surviving progeny came from, and the exact pattern of relationships at the time. In the millennium 1000 to 2000 AD, there are still a great many uncertainties and complications concerning human demographic growth and movement.

So who my ancestor in the male line may have been in the last thousand years is arguable. He may have been a trader who never went back. Perhaps he was one of the many foreign mercenaries recruited by one or other of the Warlords down the millennia, or even a travelling friar prone to human temptations. He may even have been in the Atlantic Isles immediately after the last Ice Age. What the DNA will begin to suggest if enough samples are found for analysis is who some of my distant cousins might be, and this will narrow the number of possibilities. In any event by this stage the potential number of the ancestors is very large indeed. If a person has found one or more members of the elite groups by the 16th or 17th Century, the chances are that by 1100 almost all the then elite will appear in the family tree, as one commentator has put it, half the population or more will have King William I, The Conqueror of 1066, in their ancestry.

Phase Three – Post Roman to 1100

In this period, roughly taking in “The Dark Ages” we have very few documents, and while some of these may refer to other peoples and groups they have to be approached with a great deal of care as their information is often distant in sources, loose in description, generalised, and far from being impartial. Yet a great deal of historical writing and theorising has imposed perceived structures of population and the analysis of archaeological research since the Renaissance on these shaky foundations. Because little is available, and is written by men of religion, it does not mean that we can place greater reliance on it.

Whilst we have learned to change our minds about much in science, astronomy, and medicine, in terms of the demographic issues in History there still exists a substantial vested interest in past theoretical structures and the classification of information. Giraldus Cambriensis (Gerald of Wales), of Norman Welsh immediate descent, may be an attractive writer and persuasive in his prose, but this does not make him a reliable commentator. That another cousin of the same family, Maurice Fitz Gerald, was the progenitor of the large Irish Clan of Fitzgerald, does not make his ancestry Irish.

In the third phase my father’s forefather could be an Icelander, the Sagas etc, a Pict, one of the Irish based Viking raiders that rowed up the Severn in the 890’s, a Norseman, a Gotlander, a Frieslander, a Dane, or a Saxon or any one of quite a few other things. The Haplogroup of my male DNA is found across Europe, into the Balkans, with scatterings further beyond. There were some settled in Transylvania and the Balkans, and a few of them arrived in the Scottish Borders and the West Midlands as Dacians and others recruited by The Roman Empire. It is found in Afghanistan, albeit a minority and beyond.

The idea of my forebear being some kind of Siegfried waving his sword about, or a bold Viking doing the usual things has attractions for many. The majority of my personal ancestry by 1600 probably is Scots, and they have their own ideas, some conditioned by the terms of the Scots Declaration of Arbroath of 1320. This claims “expulsis primo Britonibus et Pictis omnio deletis,” which, however translated, gives a survivor of the 20th Century a very queasy feeling. The references to Norwegians, Danes, and Angles suggest that they were not welcome economic migrants. Also, it is addressed as submission to a Pope in Avignon then currently engaged on a major Crusade against his local Jews in southern France, eliminating any who he considered to be dissidents, conniving at the sale of heretics as slaves in Islam, and burning and pursuing the fleeing Franciscan Scholar followers of John Duns Scotus, who may well have come from Dunwich in Suffolk, where an East Anglian Scott family was prominent. So what I might like to have as an ancestor, who I did have, and their personal habits and actions may be different things.

Phase Four - Roman Britain & The Iron Age

But what were Vikings, Saxons and others before these labels were applied? The few writings of the period we have inherited are anything but clear, and modern archaeology is suggesting that what went on in the settlements was quite complicated. Similarly the story of the Roman and the immediate earlier period is becoming much more complex, there is scanty written information, and the naming and characterisation of the peoples and tribes encountered beyond the Imperial fief is vague and loose. A real problem is that this information from the Classical Period has had a major impact since the Renaissance, with again too much trust placed on too few sources. Before then in Northern and Western Europe we have only the findings of archaeology and the application of science. This has developed so rapidly in the last three decades, that much of the theorising and the ideology of historians, antiquarians, and eugenists made in the period 1700-1970, that is still imposed in many academic circles and in groups myths of origin has to be discarded. But the imposition of old theories and systems are difficult to shake off. My preference is to use the simple term “early peoples” until a great deal more is known.

Just who were the Germanii, the Goths, Visigoths, Vandals and others? How do these earlier groupings fit in to the pattern? Then, there are the Celts, an alleged all conquering Master Race eliminating native populations, presumably by the usual methods. If they were not this, and there are grounds for thinking that matters were much more complicated, are we using this term as a catch-all that has been assumed as a racial theory? Given the movement question then it begs the question of whether many of the later Saxons, Franks and Gauls were just another type of “Celt”. If there are serious difficulties in the analysis of the Iron Age and the later Bronze Age then in the times before it is necessary to be come even more careful and less dogmatic or wedded to an 18th Century and 19th Century methodology. The belief in Britain and Ireland by many that the “Celts” wiped out the previous populations to become the only Pre-Roman race in these territories is a sub-set of the early theories of an Aryan master race, and consequently has to be approached with a very critical eye.

We may have begun to learn a great deal from the benefits of the applications of science in terms of the food they ate, the metals they used, the way they built their houses and farmed, and other things. But we can only speculate about the languages they spoke, the gods they worshipped, their belief systems, how they saw themselves, or how they regarded their history. We can be surer that they knew mathematics and the way of the stars in the sky, but less so about the purpose. For myself, my ancestry is likely to be amongst all or any of them.

The Early Four Phases – The Bronze, Neolithic, Mesolithic and Palaeolithic Periods

In the early, called pre-historic times, the early Iron Age, the Bronze Age, the Neolithic, the Mesolithic and the long Palaeolithic there is no documentation for much of Europe, as well as other parts of the world. There are remains in the Mediterranean Basin, the Near and the Far East that give us an insight into language, society, and the economy of a number of peoples. In Britain and Europe in the mid 19th Century the rediscovery of the ancient world of the Near East beyond the time of the Greeks and Romans, and the decipherment of their languages with the accompanying information from these earlier societies took a long time to find acceptance. This was because whole systems of belief, theology, and the myths of peoples rested on only what had been known, and for many solely in the history recorded in The Bible. So there was denial, and the attempt to insist on fitting every finding into an existing theoretical structure.

But elsewhere only what is found and reclaimed from the soil and the scientific analysis and classification of those findings is available to us. In the last thirty years, new developments, new methods, and new science have transformed much of the dating and analysis of discoveries, and of past findings. The DNA research is attempting to provide, if not an answer, at least a means of addressing some of the issues of human occupation.

Inevitably, in the analysis of human DNA from existing populations there is a debate, with a divide between those who want to prove the continuing validity of the early theories of race and descent, and those who feel that these are inadequate or plain wrong as an explanation of the development of modern humanity.

For the lands beyond the Atlantic, now the Americas, the “New World” seems to be becoming much older than anticipated, and more complex, and illustrative of some of the problems. As the Ice Sheet covered much of North America the initial theories that became established were that the settlement of The America’s originated only after the Last Ice Age with migrants from North East Asia across a previous land bridge and later the Bering Strait who made their way south over many generations. In the USA now there are groups who have claimed the description of Indigenous People and who bitterly oppose any findings or attempt to research or reconsider any further past. Alongside them is an academic establishment alarmed that matters might be more complicated, and that there were both earlier and other peoples. So there are moves to suppress work that could challenge these beliefs. Also, little attempt was made to find anything from earlier periods because it was assumed that there was nothing to find, or to look for other peoples because the theory said they did not exist, much in the way that the concept of the circulation of the blood was once disregarded by the most learned physicians, and of course, we all know that theoretically it is impossible for bees to fly.

Coda

Given that the Ice Sheet came down to what is now the English Midlands, my male ancestor may have just stayed where he was and changed with the times or have come from one of many places. Where he may have been and what form of life he adopted, can only be guessed at. There was one of my name transported to America for theft in the early 18th Century. He would have felt that he had been sent to the ends of the Earth. But when he arrived there he would have found a local tribe in the vicinity, and he would have recognised the name.

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