These days it has become very popular to have one’s DNA analysed via a spit test so that one can trace one’s ancestry and (hopefully) to find links to famous people in the past. There are numerous companies providing genetic ancestry tests and charging $50 and upwards.
Unfortunately, many of the claims regarding one’s ancestry put forward by these companies are wildly exaggerated. They are generally based on evidence from other fields, archaeology or linquistics for example, rather than the DNA signature in itself.
The reason for this is that, a) the results on which these claims are made are all based on data from populations either living or recently dead and b), the DNA analyses in their data base are from people living in Europe or North America. Hence, the data is highly skewed.
The fact is that the amount of DNA any individual inherits from a relative only a few generations back in time is negligible compared to the vast amount he or she inherits from all their other ancestors.
Put in another way, even though you could prove, through written or other evidence, that you were inherited from William the Conqueror (who invaded England in 1066) this wouldn’t show up in your DNA profile.
I have to admit that, a few years ago, I fell for the blurb from one of these companies and sent off for a test. My results showed that on father’s side we were descended from the Picts, some of the first inhabitants of the British Isles. On my mother’s side we are descended from people who survived the freezing conditions of the last Ice Age in caves in southern France and Spain. Having Scottish ancestors on both sides, no surprises there!
All I’m saying is that, though the results of your DNA test may provide some entertaining reading, the results should be taken with a large dose of salt. If you want to find out about your ancestry you would be better off digging around in the loft.
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