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DNA-Genealogy makes it possible for you to research your family tree with the most modern methods. It makes fast and exact research into your family history possible, whether as your first venture into researching your ancestry or as a supplement to traditional genealogy. Where traditional research into your ancestry examines birth, marriage, and death certificates, a simple saliva sample is all that's needed for DNA-Genealogy. That's because each of us carries with us the most important and exact set of files needed: our DNA.
What is DNA?
DNA is a molecule, that contains the genetic instructions for all of the functions and substances of the human body. It looks like a spiral staircase. Each stair step is made up of two bases. There are four different bases: Guanine, Thymine, Cytosine and Adenine. If you envision the bases as coloured Lego pieces, then there would be four colours and each step would be two-coloured.
The total DNA of a human being is called a genome. It contains the genetic instructions for all of the functions and substances of this body. We inherit the genome from our ancestors. It is re-combined in each generation from the genes of our parents, so that genetic traces gradually get lost.
There are only two areas where the DNA is not re-combined:
1) in the Y-Chromosome, which is passed on from father to son, and
2) in the DNA of the mitochondria ( mitochondrial DNA), which all children inherit from there mother.
How can a family be genetically distinguished?
The DNA of all human beings is up to 99.9% identical. The remaining 0.1% are the source of the individual differences (e.g. eye colour, risks of certain illnesses, or deviations with no discernable function). Once in a while, there are non-functional sections in DNA, a coincidental harmless change called a Mutation. All descendants of that person will inherit this same mutation. If the same mutation shows up generations later in the DNA of two people, it is apparent, that they have a common ancestor. Mutations build the basis for the construction of a genetic family tree.
How can DNA say anything about my Origins?
Comparison of mitochondrial DNA (mtDNA) and Y-chromosome DNA of people from different people groups provide geneticists with an idea of when and where these groups have travelled in the migrations of peoples around the world. Mutations do not merely mark individual families, but also entire sub-populations (population groups). When one researches the occurrence or frequency of certain mutations (markers), one can sub-divide the complex family tree of the human race into individual branches.
If a people group migrates, or lives for a long time in geographic isolation meaning that there would be no genetic exchange with other groups then it develops its own mutation pattern. It becomes a haplogroup with genetic characteristics, that are unmistakeable. Each one of these groups stands for a branch of the human family tree: In Europe, for example, other haplogroups are distributed than in Africa or Asia.
Even social and religious traditions leave their traces behind in the inherited genetic material, since the members of some groups preferentially marry among themselves. Although, for example, Celts and Germanic Tribes often encountered each other, there were hardly any intermarriages. The same is true, for example, of Jews, who lived in isolation for centuries and have thus preserved specific genetic characteristics.
Even when written history falls silent, DNAGenealogy can further research and decipher the history of humankind. Thanks to the socalled molecular clock, the point in time when two lines divided and the epoch in which their last common ancestor lived can be determined. Analyses of genetic material also reveal the Wanderlust of the first humans. Researches discovered remarkable similarities between the people groups in India, Oceania, and Australia, as well as between Siberian peoples and Native Americans. Thanks to the molecular clock, we can not only determine the point in time and the origin of the migration, but also how the peoples are related to each other. This is how, for example, the ancestral origin of the Basques was discovered.
What will be analysed in a DNA-Genealogy-Test?
You can imagine mitochondrial DNA or the Y-chromosome as the genetic coat-of-arms of a lineage. Every member of the paternal line carries the same Y-chromosome, like a heraldic stamp. Over the course of time, this stamp is copied over and over again, and the engraving fades, so that the family's coat-of-arms is no longer clearly recognizable. The DNA acquires new mutations, so that the DNA-profiles of close relatives are more similar than those of two men with a common male ancestor who lived 600 years ago.
THE Y-CHROMOSOME
Chromosomes consist of DNA and proteins. Each cell of the body has in its nucleus 23 chromosome pairs (Exception: egg cells and sperm cells each have 23 individual chromosomes). One of these pairs is the sex-chromosome pair. Women have two Xchromosomes, men an X- and Y-chromosome. The Y-chromosome is passed from father to son unchanged. Every man inherits therefore his genetic coat-of-arms in the male line from his father.
In a DNA-Test, certain known DNA sequences (markers) are looked for. These markers are referred to as DYS and have different gene variants (alleles). The alleles are identified with numbers, which recapitulate the number or repeating sequence segments of that marker. In the illustration, for example, the marker DYS393 the allele value of 13. That segment of the sequence repeats itself 13 times.
