Four years ago I began my DNA tests, hoping to find some new clues about my family´s origins. Since then I have ordered more tests to expand and refine the results. Much new information has come forward, but the work is still by no means complete. Recently I had another DNA test which will doubtless open new and interesting lines of investigations. In recent decades the archives already had been studied thoroughly to discover the history of family Hjelt. But in our DNA we have an archive also, written by Nature, and studying that archive has just barely begun. Genetics, along with archeology, linguistics and demography can reveal more and more detailed stories about the lives of our ancient ancestors and their migrations over the centuries and millennia.
My first DNA test results applied, of course, to ancient times, but were still really interesting. First of all, it became clear that the ancestors of our family had come to Finland from the west relatively late, probably only after the Swedish settlers of the 1200s. The test showed that the Hjelt family men belong genetically to a group which is fairly rare here in Finland, but more common in Scandinavia and which comprises a majority of Western European men.
Before I describe in detail how I have interpreted my DNA results, here is a short introduction to how Nature writes its stories in the DNA chain.
Snips
There are different kinds of DNA tests which are used to trace the origins of a particular population and to aid in genealogical research. Because this blog applies to tracing the patrilinear line of our family, only one test type has significance--namely, the Y-DNA test, where only the Y chromosome, which is transferred from father to sons, is studied. Geneticists have chosen sections in the DNA thread where the frequency of the mutations is known with some accuracy. There are two types of mutations to be examined, one of which is called SNP (Single Nucleotide Polymorphism) or "Snip". In later writings the other type of mutation is discussed.
A Snip is a mutation in which one nucleotide in the DNA chain changes to another. The scheme (see over) shows an example of how the nucleotide CG changes to TA. The nucleotide sections to be examined have been chosen from the so-called "junk area" of DNA, which is about 95% of the chain, and these nucleotides are not located in the areas of DNA that form genes. This is important because the public comparison of results is essential for getting relevant information.
The time between mutations in a particular location is very long, by which we mean houndreds or even thousands of years. According to snips the tested men are classified to so-called haplogroups. The geneticists in turn have built of them a so-called haplotree where the mutations (snips) branch out, forming a kind of hierarchical genetic map. With the help of haplogroups, among other genetic genealogy studies, we can begin to uncover the ethnic origins of individual human beings, the migrations of populations and their ancient histories.
Haplogroup R1b
Haplogroups of Finnish men have been surveyed in a study (Lappalainen et al, 2006). Four of the most general haplogroups and estimates of the places and dates of their origins are:
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| Proportion of R1b men in Finland |
N1c 58,2% South-Siberia ~12.000 BC
I1a 28,0% Europe ~3.000 BC
R1a 18,0% Eurasia >16.500 BC
R1b 3,7% West Asia <16.500 BC
The men of the Hjelt family belong to the group R1b. On the enclosed map is shown the proportion of Finnish R1b men in different areas. Accordingly proportions are shown in other parts of Europe as well as in Asia and Africa (below). As one can see, the Hjelt men in Finland represent a fairly rare haplogroup there, however it is the most commonly found in Western Europe.
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| R1b men on the Old Continents (Eupedia) |
The following diagram is a presentation of the R1b men's haplotree. This part of the haplotree diagram is quite stable, but the full haplotree is considerably more detailed in its root parts and it changes continuously. The complete R1b haplotree alone is divided into about 550 parts. The geneticists' international organization ISOGG checks the structure every year and makes additions to it in accordance with newest researches.
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| R1b Haplotree (Based on Eupedia) |
The main body of the haplotree consists of a hierarchical structure and branches between the mutations, that is snips. I have marked them with black. The Green color is used to show the timeline that is composed of prehistoric periods and the blue color describes the geographical areas on which it is thought that the mutations have taken place. The Red color shows the names that are generally applied to the haplogroups.
My haplogroup and the haplogroup of all the men of the Hjelt family is indicated today shortly as R-DF27. This group is commonly known as the Ibero-Atlantic group (more about it later). This designation describes our place in a large-scale haplotree. The label is short, pithy and descriptive. One could even consider printing it on a tee-shirt. To distinguish my haplogroup from that of other men who have had their DNA tested, I must describe my haplogroup more precisely, taking into consideration the subclades under DF27 that are still common to all Hjelt men. The full expression of my haplogroup is R-DF27>Z196>Z209>Z220>S21184>S19290. This more complete description has become common only during the last couple of years. It is worth noting that the earlier less complete designation still persists in books and articles. The old type of label was built so that the branches of haplotree are along in the note. In the course of time the use of this kind of a note became unwieldy because its length and changeability. Consequently my haplogroup has been written R1b1a2a1a2a1a1 only four years ago, but after that it has changed again to R1b1a1a1a1a3b1.
In the following articles I will trace my ancient ancestors' footsteps first from their roots in western Asia, continuing into Eastern Europe and on into Western Europe, the Iberian Peninsula (perhaps) and finally toward the coast of the North Sea.
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T. Lappalainen et al.: Migration Waves to the Baltic Sea Region, 2007
Eupedia Genetics, Articles written by specialised authors.
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